The work of the Division of Insecticide Investigations, 1927-1939

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Title:
The work of the Division of Insecticide Investigations, 1927-1939
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United States -- Bureau of Entomology and Plant Quarantine. -- Division of Insecticide Investigations
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U.S. Dept. of Agriculture, Bureau of Entomology and Plant Quarantine, Division of Insecticide Investigations ( Washington, D.C )
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41







DEPARTMENT /
-.516A November 1940










TE WORK OF THE DIVISION OF INSECTICIDE
INVESTIGATIONS, 1927-1939



Contents

Page
Introduction ................................................... .. 3
Acknowledgment ......................................................... 4
Insecticides of plant origin ..........................................
Tobacco ......................................................... 6
Pyrethrum ....................................................... 8
Derris, cube, and other rotenonm-contsining plants ............. 10
Derris ...................................................... 10
Lonchocarpus ................................................. 12
Tephr s'ia ...................................................... 12
Spat holobus ........................................... 13
Paroselao (f m .y Fabaceae ....................................... 13
Quas .ia an' A'schrion (family Simaroubacene)................... 14
Croton (family _phorbi ceae) ................................... 14
Ealo~ h -Ttnn familyy Apocynnceqe) ................................ 14
Phelloaendron (family Rutacene) ................................. 14
IFelaniIa (fanlly Compositae) ..................................... 14
Anamirta (family Menispernpcee) ........................... .. .......... 19
Anabasis (family ChenoTmdiaceae). ............................... 15
Miscellaneous insecticidal plants .............................. 15
Synthetic organic insecticides ..................................... 15
?yrf.dine and pyrrolidine derivatives ........................... 15
Thiocyanates ................................................... 1I
Halogenatad organicc compounds ................................. 1
Dinitrophenol and derivatives .................................. 16
Azo compounds ................................................. 17
Heterocyclic compounds containing nitrogen and/or sulfur ....... 17
rhenothiazine ............................................. 17
Phenothioxin (phenoxathiin) ,............. ...................... 17
Dimethylacridan ........................................... 19
Phenazine ................................................. 19
Xar.thone .................................................. 1
Miscellaneous synthetic compounds ..................... ......... ... 1
Relationship between toxicity and chemical constitution ............. 19






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Pe
Inorganic insecticides ............................................ 20
Lead arsenate ................................................ 20
Calcium arsenate ............................................. 20
Paris prepn end homologs ..................................... 21
Other Arseuicals ............................................... 22
Fluorides ......................... ................................ 22
Mercuric chloride ............................................ 23
Copper compounds ......... .....................................23
Sulfur ....................................................... 23
Spr y residues .................................................... 24
Fuigants............................................. 29
F or ates ... ................... ........................... .... 2
7thylene dichloride and propylene dichloride ................. 2g
Ethylene oxide ............................................... 29
Chlorspicrin .................................................. 29
Fydrogen cyanide ............................................. 29
Chlorine ...................................................... 30
Accessory materials .... ................................................... 30
Letters and spreaders ........................................ 30
Diluents ......................................................31
tickers ..................................................... 31
3mulsifiers .................................................. 31
AnalyticPl investigations ..................................... ... 31
Application of statistical methods to insecticide problems ........ 34
New end improved al;aratus ........................................ 35
Chemotropism ...................... ................................ I
Ph rnacolopical invostipations .................................... 37
Mothproofing ....................................................... 37
Tree medication ..... .............................................. 3
economics of insecticides ......................................... 38
Bibliographies, abstracts and reviews ........................................ 3
Abstracts of patent literature ............................... 39
Book reviews ..................... ................ .............
Popular Prticlos on insecticides ............................. 40
PaRpers prepar,'d b7 invitpti-n ................................





-3-

INTRODUCTION

On July 1, 1927, two of the burnaus in the United Stites Dr'ra-tr'nt
ef Agriculture, namely, the Bureau of Cheriistry and the Burenu of
were consolidated to form the PureAu of Chpmistry F nrd Soils (now 1mown as
the ?ureau of Agricultural Chemistry and Enrinoering), and at thp sepra time
the Division of Insecticide Inv&qtiations wns created rn one of the units
if the new bureau for the purpose of proecutin, chemical ree',rch o-n in-
secticides and fungicides. On Septembo 1, 1P3)4, this Division w, tr.na-
ferred te the Bureau of Entimolngy ani Plant Quarntine, end hnp remvined
in this Bureau since that time,

The authority for the wor- of this Di7iqtrn is contiinod in the vnri-
our appropriation bills for the Dopartment of Arriculture Pnd re'r-d in Part
as follows:

"Insecticide and f'lnricid' investigntions: For the in-
vestigation and development of methods of manufacturing irsec-
ticides and, fuingicides, and for investipatin chemical problems
relating to the composition, action, and npplic'tion of irsec-
ticides and funpicides."

The organization and research line projects of the Division of Innec-
ticide Investigations as of December 31, 1739, are choivi in the chirt which
follows page 2.

Diuing the 12 1/2-year period ended _,ecmlbhr 31, I t)39, th7 nivirion
of Insecticide Investigations has publibhd. 4 0 prpers, qnd its mprbeirs
hq.ve been erpnted 60 patonts. Other pspers Pnd p-tnnt Ppplications nre
pending, as shoWn in the following tpbulntion:

Status of publication, Drc mbrr 31, 1 39

P.pers published ............................. .11-O
Papers approved, but not y.t published 19
Papers submitted, but not yet -pproved ..... lq
Total .......... ............

.Patents granted ............................. 60
PvAtent apIplications ir interference ........ 2
Patent applications pcnding ................ 3.
Total .. .................... 9

The vpprepriation allotted the Division has r,-nzed from $74,FOO for
the fiscal year 1929 to k16l,269 for each of the fiscal yeors 1937 and ].939.
A detailed. report is Fs follows:

Approprin t ions

Fiscal year Totpl eppropriatien

1929 $ 3 o4, o0
1929 6o,300
1930 1)l,765
1931 1S,(Y1on
1932 129,400





- 4 -


1933 137,300
1934 0 3,00 0
l]i55 132,352

1937 161, 2r9

19 12,569

Tho following ncco-nt of .cc= -lshments'r s bien mpndve r)s brief ns
is compnti1le wih elerit-', Lh- n-vb're in 1),ronth-ses ar tha index num-
bers of tnc' v.blic-tio.s -of the DiTi1sio a comn litF lit of which is
arr to this report. 'Un itP S t ts p,,t,3 t E ~r nt r n c mh(-rs o f t h
Division 'e r~f'r~c to urdc;r their oiom nu.ThPr Fu-l dt1Pi, of a.ll
r sroh work done in the Division will be foun(I in thnr publications
and pntr-nts.

A C -:N0GMT

It sF-ould be emr'rqizeoA 4at t>i w-rk of the Division of Insecticide
Investipntions is wholly Dhyo:i l nn- hemical Pni thnt it mnkns no tests
upon insects, ci ir te l,.bor,-crv or in tho fiiFld. All tests of
msteri3.s to 3etrmnie t 'hir in c-'T c-JT VrU rfprrre* to ir. this report
were rnre iy rer2err of otheo divi~io's of the :;ureiu ef ?ntomoloF,, Pnd
Plant Quar.ntine. urte-7.ore, r-any af the u' -,e. che ical studies, es-
peciallyr of analytic,-! r-oos ~aad of prores-es of waning a9~les, have
been c-rie@ o't i coo-rprti-n "-i chemistr-, hortic-lturists, Pnd others
int c o i turai C1o.istrr and "n~ine rin, tho Food Pnd Drug
Admini-tration, the Threr of Plant Induitry, and certain Sontct agricultur-
al e.->erimrnt stations. !uch of the worr of the "Oivision of Insecticide
Investint'o-s hrs been cocperative, is shown b- the fact that Ilr7 out of
48O pi'blil, d n-pers and 3 ot of 6', patents represent the joint efforts
of our worle: rs with thore in other orzrtnizations.

A summery of this coonerative work is indicated below. The names
of the coo'-rr-tin, entomlooist? Pnd other scientists ,rp nlco indicated
by acterisks in the list of publications at the end of this re-port.
Co%.Tr-tive wek with various or niz-,ti'ns, qs shown by number

of ii r tic-ni and patents issued jointly with each worker.

United states Department of Agriculture.

Bureau of Entomolory and Plant Quarantine:-

Divi ion of Insects Affoctinp'
M3.n and Animals:
Number of
publ icat ions
Back 2
Bishop 3
Lake 3
?armnn 3







DEPARTMENT OF AGRICULTURE

BUREAU OF ENTOMOLOGY AND PLANT QUARANTINE

DIVISION OF INSECTICIDE INVESTIGATIONS

ORGANIZATION CHART
JAN. 1, 1940

R.C.RGOARK-IN CHARGE P-8
C.M. SMIT- ACTING IN CHARGE P S
S R.Gersten CAF-5
S.A. Davidson CAF-3
RO. Eric..on SP -4
M.Iverson SP I
M.L. Allen u ?-T


I
INSECTICIDAL
PLANTS

H L Hailler P-6
Project Leader
Miscellaneous Plants
E. P.Clark P-5
M.S.Schech+er P-Z
J.P Hewlett SP-4
Pyrethrum
F B La Forge P-5
F. Acree P-Z
robacco, etc,
C R.Smith P-4
L N Markwood P-4
Rotenonc bearing plaits
L0O.Goodhue P-3
J W.Wood SP-4
&eraniol
HA. Jonmt P-3
J.W Wood SP-4


I
SYNTHETIC ORGANIC
INSECTICIDES

H.L.Hailer P-6
Project Leader
Organic Compounds
in general.
L.ESmlth P-4
C, V. Bowen P-Z
S 1. Gertler P-Z
M.S Schechter P-Z
Phenothiazine
L E-Smith P-4-


I
INSECTICIDAL
DEPOSITS

CM.Smith P-5
Project Leader
Miscellaneous
R H.CArter P-3
Arsenicalis
R H.Carter P-3
C.W. Murray P-3
H. 0. Mann SP-4
Fluorides '
R H.Carter P-3
Nicotine
L.N.Markwood P-4


I
INORGANIC
INSECT ICIDES

CM.Smith P-S
Projec+ Leader
Calcium Arsenate
o ANelson P-4
Sodium Arsenite
O.A. Nelson P-4
White Arsenic
FE .earborn P-3


I
FUMIGANTS

C.M.Smith P-S
Project Leader
Hca-dispersion of
relatively Non-volatile
Inaecficides
L 0 Goodhue P-3
JW. Wood SP-4


I
ACCESSORY
MATERIALS

C M Smith P-5
Project Leader
SpreadersWelters, Ci
WIL Cupples P-4
Adhesives for OrSanic
Compounds
H L Cupples P-4


I
TOXICITY
STUDIES

C M.Sith P-5
ProWsct Leader
Tests on Goldfish
W.A Ge rsdor'ff P'-3


I
ANALYTICAL
INVEST IGAT ISM

C N Smith P-S
Project Leader
Analytical Service
R H Cartoer P-3
C W Murray P- 3
o L.Vlvian P-.
HI 0 Mann SP-4
Chemical Meh4od,
RN, Carter P-3
C.W Murray P-3
O L.Vivian P-Z
Ph sical Methods
E L-Gooden P- I


I FIELD LABORATORIES


I
MOORESTOWN, N J.

R 0. Chisholm P- 4
In charge of laboratory
Insecticides for Ja lpnese Beetle
R.D Chisholm p-4
Chemical Estimation of Effective-
nesS oi Treated Soil
R D.Chisholm P-4
L Koblitaky P-I
Analysis of Control Samples
L Koblitlky P I
R.W.Coles 5P 3
J.J.Lockowitt SP-3
Analytical Methods
R.) Chisholm P-4
L.Koblitsky P- I


VINCENNES. IND.

J.E.Fahey P-3
In charge of laboratory

Insecticidal Deposits
J.E Fahey P-3
J F Cassidy P- I
HW. Rusk SP-4
Insecticides for CodlinS Moth
J CEFahey P-3
J. F. Cassidy P-I
H.W. Rusk SP-4


I
MANHATTAN, KAN.

H. DYounS P-3
In charAc of laboratory

Fumigation of Stored Grain and
Cereal Products
H. D. Youns P- 3


I
WHITT IER, CALIF.


YAK#MA, WASH,

C.C Caseil P 3
In c"ar of laboratory

Insecticidal Dep"oai
C C Cassll P-3
ln3"ticide for Codling Moti
CC Cassil P-3


R A Fultin P-4
In char of 13boratory
rumination of Calif. Red Scale
V A Fulton P- 4
R. L. Busbey P-Z
Sulfur
R A Fulton P- 4
R L. Buabey P-2







Number of
Division of 6ntrol Investiti on: Pu blications
Bulger 1
Campbell 7
Fink 5
McGovran 1
McIndoo
Phillip3 1
Richardson, 0. F. 1
Richardson, F. F. 1
Shepard 2
Sullivan 12

Division of Cereal and Forage Insect
Invest ig ti~ns:
Cotton 17 (+ 3 ptents)
Wapner 9

Division of Fruit Insect Investientions:
Cressman 3
Fas I
Lathrop 1
Mung:er 6
Newcomer 4
SGzama 7
Siegler 9
Steiner 9
Sunmerland 1
Yothers 1
Yust 2

Division of Truck Crop and Garden
Insect Investigations:
Davis 4
Weigel 1

Bureau of Plant Industry:
Diehl 3
Hailer, M. X. 4
Leukel 2
e eve s i
1~yal 5
Smith, Edwin 3

Food and Drug Administration;
Abbott A
Clifford 1
D vi'.lon, W. M. 4
Graham 2
Harris 1
Hillig 2
Keenan 5
Lnuhrey
'McDonnell
Vorhes 1
Wichmann 2








Number cf
Bureau of Agricultural Chemistry lpubli.caticna
and Engineering:
Davidson, J. i
Palkin I
Pulley 1

Machine Shops:
Swenson, R. T. 1

Bureau of Agricultural Economics:
Cox 1

Maryland Agricultural Experiment Station:
Be au zont 3

University of Maryland:
Haring 1

West Virginia Agricultural Experiment Station:
Gould 2

INSECTICIDES OF PLANT ORIGIN

Beginning in 1927, research has been prosecuted on the principal in-
secticides of plant origin such as nicotine, anpbasine, rotenone, deguelin
and related rotenoids, quassin, and pyrethrins I and II. Exploratory work
has been carried on with many plants, including, Nicotipnp, Pyrethrum, Derris,
Lonchocprpus, Tephrosin, Spn.tholbus, Firosela, Qu)ss~I, Aeschrion, Croton,
He plophyton, Phellorer'-n, vel;niiiim Aniirta, anri others in an effort to
find new compcuns -f insocticilal value.

The results of this work are discussed under separate headings.

TOBACCO

Tobacco (Ficotinna tabacum L., family Solpnaceae) is the only source
of the widely used and potent insecticide nicotine. About 1,000,000 pounds
of this alkal-id, are consumers annually in thp Unita States, mostly in the
form of an aqueous soluti-'n of the sulfate containing 0 percent of nico-
tine. Nicotine i- not only a contact insecticide and a fumigant, but when
made into certain wnter-insoluble forms it is also a valuable stomach
poison for some insects. The Divisi- n of Insecticide Investigations has
been active in the search for new nicotine compounds and new and better
ways of applying nicotine against pests. New uses for nicotine help far-
mers, orchardists, florists, and poultry raisers to better control of their
insect enemies and also widen the market for surplus and off-grade tobacco,
thus aiding the tobacco grower. The United Stntes, luring the 3-year
period 1935-37, prDA'iiced nn average crop of tobacco amounting to 1,335,296,O0o
pounds, or about 23 percent of the world pr-,aucti-n. The estimated farm
value averaged nearly 277 million dollars. Because of reduction in exports
of fire-cured and dark air-cured tobaccos, unsalable surpluses have devel-
oped since 1929. Of means proposed to reduce these surpluses an increased






-7

consumptin if tobacco as a source of nfcotine is the most -promising, end
the Division -of Insecticide Invest;atori hrs contributed notably to this
end.

Our accomplishments in these endeavors include the development of
the new nicotine compounds nicotine psat (236, 351, 410, Pnd U. S. Potent
2,107,058) and nicotine h-mate (297 aiid 7. S. ?at, nt 2,066,941) by Markwood,
and nicotine bentonite (222 and U. S. Patf-nt 2,0F6,56R) by C. T. Smith.
The latter has given promising results in orchard tests in Indiana (Otoiner
and associates, ana Fahey, 394, 4C5, 447) and elsewhere aa a substi-
tute for lead arsenate for codling moth control.

The removal from apples of nicotine-bentonite spray residues was in-
,vestigated at Vincennes, ind., by Fehey, Ruvk, Steiner, aiLd Salnqa (407)
and at Yakima and Wenatchee, Vs sh. by Carsidy of this 3ureau and Edwin
Smith of the Bureau of Plant Industry (65). Either hy ,,cochloric acid or
sodium silicate washing solution is effective in removing these residues.

The increased use of nicotine (and, in turn, of tobacco) dueto the
development of this new nicotine compound for codling moth control may be
seen from the, following figu-re of the recent consumption of nicotine in
the apple belt of Indiana and Illinois.

Consumption of nicotine for codling
moth control in Indiana ad Illinois

Year Pounds (of alkaloid)
1936 4cc
1937 4, oo0
1938 4nnoo
1939 g0,000

The possibilities of a still greater use of nicotine as a substitute
for'lead arsenate as a poison for codling moth control are apparent when it
is realized that the greater part of the annual consumption of about 4O
million pounds of this arsenical in the United States is applied in apple
orchards.

The Secretary of Agriculture (Senat3 Document Yo. 39, 76th Congress,
1st Session)-in a letter dated March 17, 1939, transmitting in response to
Senate Resolution No. 291 (75th Congress) a report pertaining to the export
trade in and byproducts uses of tobacco, wrote as follows:

"Nicotine bentonite used as a poison for chewing insects
establishes a decided step forward in insecticide science.
Its use is believed to involve no objectionable residue
problem as is -the case with arsenate of lead, now the most
widely used poison in the horticultural field. A further
advantage in the use of this material is that it does not
damage the foliage of the plants upon which it is employed
nor is there any accumulation of poison. in the soil. This
material has passed the experimental stage Pnd in certain
fruit areas it has been adopted in commercial procticeo *
It is estimated that if the present indicated rate of in-
crease in nicotine usage for the control of, the codling






moth is maintained, 1 million pounds of nicotine alkaloid
might be used annually by the apple-,growing industry alone
within 10 years. Such new demand for nicotine would absorb
the available supplies of the low grades in the heavy types
of tobacco, and wculd require very much larger amounts of low grades of
the lighter types such as flue-cured and burley tobaccos
than are now being consumed. Such new demands would be in
addition to the 12 to 15 million pounds of low-grade leaf
tobacco and approximately 120 million pounds of factory
wastes now used annually for contact spray purposes."

It wns observed by C. R. Smith kU. S. patent 2,033,956) that benton-
ite combines with other alkaloids and natural bases, and Markwood (U. S.
patent 2,123,24) found that peat does also. These compounds may prove
useful as new modes of administering drugs such as arecoline, strychnine,
etc., to domestic animals and man where a delayed action is desired.

New analytical methods for nicotine were perfected by Spies (317,
320), by Goodhue (374), anl by Markwood (379) which make it possible to
determine quickly and accurately the nicotine spray re>_ ue on a single
apple, or the minute quantity of nicotine vapor present in the atmosphere
of a -reenhruse thpt his been fumi7ated with this nate'ial. These data
must be known to the entcmolog'ist in order tnt an effective and economical
schedule for the application of nicotine can 16e worked out.

In connection with our studies on tobacco, other species of the
genus Nicotiana and hybrids of these with tobacco have been examined for
constituents of insecticidal value. In addition to nicotine, C. R. Smith
isolated anabasine (249) and lnevo-nornicotine (356) from certain of these
plants, and the plant breeder has been riven information which enables him
to produce a hybrid rich in any one of these alkaloids. This work has
value not only to those seeking improved tobacco varieties, but also to
those who wish to develop new and improved sources of insecticides. For
example, anabasine is at present obtained commercially only from the Russian
weed Anabasis aphylla L. (family Chenopodiaceae), and the finding ef a
domestic source of this valuable inscocticide in Nicotiana plauca will free
the United States from a foreign monopoly.

New nicotine compounds made by the Division of Insecticide Investi-
gations include its salts with alpha-bromo-palmitic and alpha-bromo-steeric
acids. These salts are more soluble in oil than in water and hence, when
added to an oil-in-water emulsion, tend to remain in the oil phase, where-
as nicotine sulfate and other nicotine salts and also free nicotine go
largely into the aqueous phase and are lost when the emulsion breaks on
contact with foliage and the winter pnrt of the emulsion runs off.

Directions were published for preparing home-mpade nicotine solutions
from tobacco (269). There were also issued bibliographies of the chemistry
and of the insocticidal uses (306, 31l by McIndoo and Busbey) of nicotine
and tobacco. These present 3,349 abstracts of published articles and com-
prise the most complete information on the subject that has been published.

PYTrrFrJM

The flowers of certain species of chrysanthemum (Chrvsanthemum







cinerariaefolium (Trev.) Vis., family Compositae) have long been known to
have insecticidal value. Under the npmp pyrethrum as much as 20,000,0C0
pounds of these flowers have been imported into ths United States in a
single year for use in the manufacture of household and cattle fly sprays,
greenhouse sprays, and agricultural dusts. The chemist is interested in
learning the exact make-up of the two princi-oles tht are responsible for
the insecticidal action of these flowers. These principles, called ryreth-
rin I and pyrethrin II, look like Flycel-ol cut have very complex chemical
structures which, if completely understood, would enable the chemist to
synthesize related materials of perhaps analopous action. A knowledge of
the structures of the pyrethrins is also necessary in order to determine
their compatibility with other insecticides and to nak 3 it possible to use
them most effectively and economically.

LpForge end Hiller developed on improved procedure for the isolation
and partial separation of pyrethrin I and pyrethrIn II (265, U. S. patents
2,0 44,502 and 2,050,974), which, in careful laboratory tests by Sullivan,
McGovren, and Phillips (406), have been shown to act differently on flies,
the knockdown being due to pyrethrin II and the kill to j:rethrin I. The
structures of these principles, although not wholly determine3, have been
revised by Haller, LRForge and Acres (763,2E2, 291, 307, 3140, 341, 355,
370, 399, 430, 443, 479), and a new constituent of .ryrethrum flowers, called
chrysanthin, was isolated and studied (362, 453) rn' fomnd to be identical
with the pyrethrosin of Thorns. The behavior of the pyrethrins on hydro-
genation was studied by Haller and LForge (3140), and the lack of insecti-
cidal value for flies of the resulting products ascertained by Sullivan
(385). One of the reduction products is an odorous compound used in the
perfume industry, namely, dihydrojasmone (Haller nnd Lprorge U. S. patent
2,096,715). In the course of this work it was showm that crystalline
pyrethrin I semicarbazone is not P homogeneous compound (329, 329), and
pyrethrin II was isolated pure for the first time in the form of its
crystalline semicarbazone.

It was found that the common field dnisy contains no pyrethrins
(Acree and LaYorge, 302). This weed r-sembles pyrethrum closely and has
been used to adulterate th: genuine flower.

A new method of determinin. pyrethrin II was devised by Haller and
Acree (263) which is quicker and more accurate than previous ne'hods. The
pyrethrin content of fresh flowers was determined (297, 326). The value
of ethylene dichloride for extracting the insecticidal principles from
pyrethrum flowers was ascertained by Gersdorff of this Bureau, and Davidson
of the Food and Drui- Administration (L3), -nd, following an announcement
of our findin-s, this solvent came into lrg.r e-scale use in the manufacture
of concentrated pyrethrum extracts. A review of assay methods for pyreth-
rum flowers was published by Roark (25); attention was called by the same
author to the incompatibility of pyrethrum and alkaline soaps (58), and
aqueous extraction of pyrethrum was found by Schechter and Haller (413) to
be unsuitable for increasing the percentage of pyrethrins in the flowers
and in the petroleum ether extracts.

In cooperation with McDonnell and associates of the Fod and Drug
Administration (6), a report on the relative insecticidal value of commer-
cial grades of pyrethrum was published by Nelson. This called attention
for the first time to the fact that open flowers are more valuable than




- 0 -


closed flowers, a finding directly contradictory to the opinion of the trade.
t."
An examination by Gertler and Faller 425) of methods recommended
for preparing home-made pyrethruin-kprosene fly sprays showed that, although
the pyrethrins are readily dissolved in the kerosene employed, there is a
loss of 27 p-rcent in thoi volume of the solution when 1 pound of flowers
is macerated in 1 gallon of kerosene and the extract decanted. In order
to obtain a solution containing- 100 mg. total pyrethrins per 100 cc. (the
minimum standard for a satisfactory fly spray) it is often necessary to
use more than 1 pound of flowers in order to make 1 gallon of spray because
of the low quality of much of the pyrethrum on the American market. In the
case of pyrethrum powder contaIning only 0.45 percent total pyrethrins --
and material of evon lower grade has been encountered -- it is necessary
to use about 3-1/2 pounds of pyrethrum powder and 1-3/4 gallons of kerosene
in order to obtain 1 g.!lon ef minimum standard fly spray.

DERRIS, CUBE, AND OTIR ROTENONE-CONTAINIING PLANTS

Derris. -- In 1927 the Division of Insecticide Investigations began an in-
vestigation of derris. At that time Japnese chemists were investigating
one of the most important constituents of derris, namely, rotenone, but its
structure was unknown, and the presence in derris of deguelin, tephrosin,
And toxicarol wns unsuspected.

Work on rotenone tesultod in the determination of its chemical struc-
ture in November ll, and an account of this was published in February
1932. This achievement was recognized in 1933 by the award of the Hille-
brand Prize of the Washington Chemical Society to Doctors LaForre and
Haller, who, with the assistance of L. E. Smith, were the first to solve
this very difficult problem. During the course of this work our chemists
were in keen competition with chemists in Japan, Germany, and England who
were also seeking to determine the structure of rotenone. Accounts of this
research were published in a series of 32 papers by LaForge, Hailer, and
L. E. Smith (35, 51, 52, 53, 61, 65, 69, 74, 52, g3, 93, 109, 115, 117, 120,
124, 125, 126, 129, 137, 139, 150, 152, 160, 190, 191, 193, l9q, 220, 223,
231, and 232) and also a general review of all the work done to determine
the structure of rotenone (179).

At the same time the other constituents of debris and cube were
studied by Clark (56), namely, depuelin (g7, 99, lO4, ll, l19, 151, 163),
tephrosin (92, 155, 171), and toxicarol (60, 1Og, 136, 144, 163, 214). Of
these deguelin is the most toxic to insects, ani the optically active form
is more potent than the optically inactive form (Fink and Haller, 296).

Racemic depuplin was found by Goodhue and Hailer (436) to form defi-
nite stablfe solvates with a number of solvents. Depuelin crystallizes from
carbon tetrachloride, chloroform, bromoforin, and ethylenelbromide with 1
mole of solvent to 1 mole of defuelin, and from bromobenzene, chlorobenzene,
and benzaldehyde with 1 mole of solvent to 2 moles of deguelin. The optical-
ly active deruelin in the roots of Derris and Lonchocarpus does not form
these solvptes. A method for the quantitative determination of deruelin in
plant material based on the formation of the carbon tetrachloride solvate
has been published (479). Seven samples of derris contained from 0.35 to
3.9 percent deguelin and 6 samples of Lonchocarpus from 0.25 to 2.3 percent,







The piwsiciJl properties 6f rotenone were investigated, such as its
dimorphism (Gooden and Ci M, Smith, 274) and its solubility in many organic
solvents (J6nes et al, 62p 366) With some of which it forms solvates (113,
332). This property is the basis 6f the A 0by metl64 now use9 for evaluat-
ing derris and cube. The combination of rotenone with Aichloroacetic acid
was patented by Jones (U. S. patent 2,103,195).

The milky sap from fresh rerris root has been used as an insecticide
for centuries by Chinese eardeners, but in those parts of the world where
only the dried root is available little attention has been given to water
extracts. Goodhue and Hpller ()40) reported P chemical examination of the
water extracts of seven samples of derris, cube, and timbo. From 24 to 41
percent of the active material can be removed by one extraction, and succes-
sive extractions remove more. When preserved against fermentation, thpse
suspensions Qf the active principle are very stable. Poth glucose and levu-
lose were found to be present in one sample. The glucosides similar to
saponin had no hemolytic power.

The value of rotenone as a mothproofing agent was discovered by Roark
in cooperative studies with Back and Cotton (85), and its toxicity to pold-
fish was determined by Gersdorff.(96). Some ways of preparing rotenone for
use as an insecticide were looked into by Jones in cooperation with Dnvidson
of the Food Pnd Drug Administration (95, 9 ), and certain procedures were
patented (1,928,256; 1,929,968). The value of kerosene extracts of derris
as fly sprays was pointed out by Cpmpbell, Sullivan and Jones (210, 215).
The use of carbon tetrachloride for extractin rotenone from plant material
was patented by Jones (1,942,104); also a process of making dihydrorotenone
from rotenone by the use of a nickel catalyst was patented by Haller and
Schpffer (193, 199, and U. S. patent 1,94,312).

Attention was called by Roark to the ,bsence of rotenone in certain
shipments of commercial derris root (98) rece-ived in 1930, and the avail-
ability of derris of high (9 to 12 percent) rotenone content on the American
market in 1938 was pointed out by Jones (441). Roth the Federated Malay
States and the Dutch East Indies can supply such roots in commercial (uanti-
ties.

The rate and extent of decomposition of rotenone under different con-
ditions was investigated by chemLcal analysis (101, 110) and also in cooper-
ation with Davidson (96) snd Campbell and Sullivan (177) by tests upon
insects; and the stability of derris spray residues under different condi-
tions of temperature, light, and rpinfnll was studied (420, 442) by spraying
several derris mixtures on glass plates and determining the rotenone in the
deposits after exposure under various conditions of temperature and light.
Derris deposits were decomposed both in the presence and in the absence of
sunlight. The rate of decomposition was increased when the temperature was
increased. After exposure for 15 days to sunlight at 32.50 F., an average
of 60 percent of the deposit was decomposed, while 73 percent was decomposed
at 70-750 F., even though the latter deposits wer- subject to the screening
effect of greenhouse glass. In the absence of light and at similar tempera-
tures there was no measurable change. However, when the temperature was
increased to 1200 F., about one-fourth of the deposit was decomposed.

The history of the use of derris as an insecticide from 1949 through
1928 has been compiled by Roark (421, 434), and its later history is being





12 -

prepared. A list of nearly 50 species of insects, belonging to 5 orders
and 2; families, that attack stored derris root or the leaves of the grow-
ing plant (43g) and a list of the netive names for various species of Derris
(448) were published by the same author,

Lonchocaru. In the course of investigatinr miscellaneous fish-
poison plants, it was found thpt rotenone Pnd deruelin are also present in
the South American plant cube (Lonchocqrpus sp.) (Clark 1, 56; Jonnes 164,
202).

A new compound, lonchocarpic acid, was isolated by Jones from I
species of Lonchocnrpus from Vonezuelp (217), and it was found by the same
investigator that the rotenone content of stored cubp root attacked by
borers (Dinoderus) was not diminished (3O).

Tophrosia. -- Rotenone was discovered in a plant native to tho United
States, namely, Tephrosip (Crpcca) virrinipnp, or devil's shoestrinp (Clark,
175). The importance of this plpnt Ps a possible source of rotenone and re-
lated insecticides was pointed out by Roark (221) and led to an extensive
investigation, still under way, of this genus by the Bureau of Plant Indus-
try. Rotenone or related compounds were later found to be present in 5
other domestic species of this genus, and their insecticidal possibilities
were studied by Jones, Cmpbell, and Sullivan (264). A South American
species of this renus, namely, Tephrosia toxicria, wps tasted for inspcti-
cidal value by Jones ond Sullivn 3527, an toTicarol was first isolated
from this species by Clark (90).

The similarity in chemical composition Pnd insecticidal action as
well as in botanical characteristics of certain renora of FPbacpae, notably
Derris, Lonchocarpus, anI Tephrosia, was pointed out by Roari (187). Bibli-
ographies on the rotenone-bearinp plants Derris (134), Tonchocarus (279,
419), and Tephrosia (327) were published by the same author; also reviews
and popular articles on them and rotenone (29, 31, 42, 76, 77, 133, 238, 244,
4114).

A careful study by Jones, Campbell, and Sullivan (245) was rsde of
the relations between chemical composition and insecticidal effectiveness
of rotenone-bearing plants. Acetone extracts of derris, cube, haiari, and
Tephrosia virginiana were prepared and tested on houseflies. The amounts
of rotenone present in the samples wpre too low to account for all thp toxi-
city.- In more than half the samples the figures by thn Gross and Smith test,
considered as representing the sum of rotenon, and Oeguelin, agreed with the
toxicity value, but in other samples they were lower. Total-extractive
values were higher than toxicity, and values based on the metVoxl content
of the extract were somewhat closer but were also too high. When an approxi-
mate value for toxicarol was subtracted from ths methoxyl figures, the re-
sults agreed more closely with the toxicity figures in general than did the
results of other determinations. It was concluded that no one chemical
determination accurately measures the insecticidpl effectiveness of rotenone-
bearing plants.

Numerous qualitative color tests have been proposed for rotenone and
other constituents of dorris and cube roots, and spverpl cuantitntive color
reactions have been developed for the evaluation of these materials. Jones
(459) in 1939 compared the results obtain by some of these colorimetric






13

methods with eadh obher and with some of the pravimetric methnds. #e con-
cluded that in evaluating derris and cube roots it is now possible, by mak-
ing use of colorimetric procetibres rnd a determinration of rotenone by the
usual method, to obtain at least approximate valnvrs for doguelin end toxi-
carol; by the Goodhue modification of the Gross and Smith color test, to
arrive at an estimate of the insecticidal value (for housnfliec); and by
the Moyer color test, to pet a rough ides of the total materials of the
rotenone type.

Cube, timbo, and derris roots yielded small quantities (0.02 to 0.40
percent) of alkaloidal material which, at a c-ncerntration of 1:10,000, was
nontoxic to nosiuito larvae (Sullivan) and hence was not further investi-
gated (Jones, 464).

A study of toxicity to the housefly of optically active and inactive
compounds of the rotenone series was reported in 1939 by Suillivqn, G':ocdhue,
and Haller (457). The toxicity tests were made on the housefly by the
turntable method of Caznplell and Sul'ivan (Soap 14 (6): 119-125, 149. 193g).
The compounds were applied both in acetone end in a mixture of a highly re-
fined kerosene and c,rc.1,hexanone (90:10). The more dilute ace'tone sprays
were prepared by aLding acetone to the original solution, and the more
dilute keroscne-cyclohex:none sprays by add ing refined kerosene. Six tests
with about 150 flies each were niede on each concentration of the various
materials. Rotenone, tenone, lavo-bet -d ihyd ro rotenone,
levo-dihydropegueiin, levodegualin concentrate, racemic ceuelin, and
racemic Oihy'rode 'rlin ,.ere tested. In acetone solution the two optically
inactive (racemic' compounds are much less toxic than are the optically
active ones, but when tested in highly refined keiosnne containing cyclo-
hexanone the toxicity of the racemic compounds is approximatel.v the same or
only slightly less than that of the optically active compourders.

At present more than 3,000,000 pounds of rotenone-b-aring roots are
imported annually into the Unite,' States, from which ar- manufactured agri-
cultural dusts for combating cabbage worms, the Mnr~icpn bean beetle, the
pea aphil, the pea weevil, and other insects attacking truck crops and
gardens. Rotenone and related. compolins (deguelin, etc..) also go into fly
sprays, cattle sprays, and horticultural sprays for combating many house-
hold and greenhouse insects.

The value of rotenone as an insecticide is due to its extraordinary
potency (as a stomach poison to silkworms it is 15 times as toxic a- lepd
arsenate, and to been aphids it is 30 times as toxic Ps nicotine) together
with its low toxicity to mammals (only one-thirtieth as toxic ns lend
arsenate when fed to rabbits). Deguelin also has high insecticidal value
and add, to the effect of rotenone in derris, Lonchocarrus, and Tephrosia.

atholobus. -- Rotenone was demonstrated to be present in a species
of Spatholobus (Jones, 176). All plants in which rotenone has been found
belong to the bean family (Fabaceae).

PAROSELA (Family Fabaceae)

Two constituents were isolated by Spies and Drake (149) from the
Florida plant Parosela barbata (Oerst.) IRvdb., but proved nontoxic to insects.





- 14 -


QUASSIA and AESCHRION (Family Simaroubaceae)

Surinam quassia is derived from Quasein Pmarn, L. and Jamaica auassia
from Aeschrion excelsa (Swartz.) Kun'ze. Po~h the species have been
studied chenlically by Clark (333, 3G5, 399) and the nature of their active
principles clarificd. Abo-at 1,000,000 pounds of cuassia wood are importeO
annually, but Ps an insecticide its use is ristricte9 l~r ely to the control
of the hop aphid. A better knowledrge of the chem-s;ry of this material will
enable the entomologist to exP n. the rnn'P of its usefulness. A bibliogra-
phy of quassia was published (Rusbey, 449).

CROTON (Family Euphorbiaceae)

The use by the Chinese of plants of this renus Ps fish poisons has
been recorded (Roark, 112). The beans of Croton ti,-lium- L., the source of
croton oil, hnve been used by tho Ch-nose ns nn insecticide Plso. A chemical
stu y of th! constituents of these bans by Spies (234, 235, 236, 342) re-
sulted in the discovery of an nnnlogous relationship between croton resin
and the active constituent of *oi.son ivy. The presonco of a plvcoside con-
taininz d-ribose in croton be-n was confirmsft by Soles tnd Drake (243).
Tests upon rolrfish showed croton r-si; to be even more toxic than rotenone,
which nt a concentration. of only 0.04 mp. per liter (1 part in 25,000,000
parts of water) kills gollfish f11 2a") minutes. (h-ton resin would. oubtless
be a vpluable addition to our list of potent organic insecticides if its
strong vesicant action (similar to that of poison ivy) dil not preclude its
practical use.

HAPLOPHYTON (Family Apocynoceae)

The Mexican plant Haplophyton ciricidum A. DO. was studied, but un-
expectel difficulty wps encountprel in is U'tinp any constituent of insecti-
ciral value. Mannitnl (:rake a&n Spies, 7) an1 ouebrachite (Clark, 200),
which hare no insecticidal value, were irleptifieti n c-n3,tuents of the
plant. In Mexico the lp2nt is uped for c) na-inP cockr7ches and other
household insects. it is pclannec! to reexaninp this plant.

PHELLODEDRON (Family Rutaceae)

The fruit of the Amir cork tree, Phrllnr nron amurpnse, was found
to be toxic to cor'linp moth larvae anrd rosnui.Io r-e in laboratory tests
made by entomologists of the Buroau. A chomeinl stidy of this plant is being
continued. The mratrini is su 2iD O by thr Soil Oonservation Service of
the Department, which iF; interested In rrowinj the tree to prevent soil
erosion.

HELENIUM (Family Compositae)

The common sneezeweed of the Southern States known as Helenium autum-
nale L. has been reported to have some insecticidal value. A very bitter
compound, helenplin, was isolotel from the plant (Clnrk, 310) nnd studied
in the hope that it night prove an acceptable substitute for the quassin of
qunssia wood, our supply of which is all imported. Studies on several
species of Helenium are beine continued, fromn three of which a new bitter
compound, toxic to fish, called tenulin (Clark, 456) has been extracted.






15 -

AXAMIRTS (Family Menispernaceae)

Picrotoxin, a constituent of fish berries, Anamirta cocculus (L.)
Wight & Am., was studied and an improved method for its extraction described
by Clark (255). Picrotoxin has been used in certain proprietary insecticides
and its possibilities for insect control deserve careful investigation.

ANABASIS (Family Chenopodiaceae)

Attention was called to the work of Russian chemists in isolating
snabasine from the plant Anabasis aphylla L. and to the identity of the
product neonicotine synthesized from pyridine Rnd this alkaloid (C. R. Smith,
121, 127).

The physical characteristics of natural anebasine were determined
for the first time by Nelson (229).

Tests upon mosquito larvae by Campbell, Sullivan, nnd C. R. Smith
(17g) showed anabasine to be less toxic thpn nicotine, but tests by others
upon aphids showed snabasine to be superior. Later, anabasine was found by
us in the southwestern Americ n plant Nicotfina plauca R. Grah. (C. R. Smith,
249), and it may be possible to develop a commercial supply of this valuable
insecticide from what is now a worthless weed.

MISCELLANEOUS INSECTICIDAL PLANTS

Lists of plants reputed to have insecticidal value have been compiled
by Roark, for the guidance of workers in this field, in cooperation with
Keenan of the Food and Drug Administration (94,112). Tests of certain plant
extracts against goldfish were reported by Spies and Drake (130, 173).

SYNTITIC ORGANIC INSECTICIDES

Except for a few compounds used as fumigants, organic materials of
insecticidal Value were, until recently, all of natural origin. Examples
are nicotine, the pyrethrins, rotenone, petroleum oils, and soaps. Of
these, only nicotine has been synthesized, anO the resulting product, being
a racemic mixture, is less active than the naturally occurring laevo-nico-
time and is, moreover, much more costly. Balked in his endeavor to synthe-
size these organic insecticides, the chemist has prepared compounds of
simpler structure but which contain some grouping of atoms found in the
more complex natural product. For example, the nicotine molecule is made
up of a pyridine ring and a pyrrolidine ring. Many Aerivatives of these
two compounds have been made and studied for insecticidal action but only
one approaches- nicotine in toxicity.

PYRIDINE AND PYRROWIDINE DERIVATIVES

Among the derivatives made by the Division of Insecticide Investiga-
tions are'the Kipiperidyls (13) and the dipyridyls (47) made by C. R. Smith
and the three benzylpyridines (17) and various derivatives of pyrrolidine
(1) and of pyridine (19) made bv LaFore. Richardson and Shepard found
that of these compounds the only one of outstanding insecticidal value is
beta-pyridyl-alpha-piperidine reported by C, R. Smith (33, gO, g9), to which
the name neonicotine was given. Later the optically active form of this








alkaloid was isolated from a weed belongiftg to the sug bdet family (Cheno-
podiaceae) by TRusian chemist# aha called Iy theta aabasine from the name of
the plant, Ahi$hsig 6ph~lhq t. (1211 12871

TI{I 0 C YJ'TAT ES

The hi7h insecticidal value of the vapors of the readily volatile
organic th!o--anatc was first discovered in the United States Department
of A;ricu'1 a7x-c (1Thi ert et al., T. S. Dept. Agr. Dept. Bul. 1313, 1925).
Later, one of these, namely, methyl thiocyanate, was found, by Lathrop, yust,
and Cupples (2148, 298), to be very destructive to the California rpd scale
when used as a fumiPant, but it proved to be too injurious to citrus trees
for practical use. Followin, this lead new thiocyanates and also isothio-
cyanates were synthesized (148, 313) and found to be hi-l1y toxic to gold-
fish. There are now marketed --is insecticides in the United, States lauryl
thiocypnate (Loro), various thiocyano derivatives of eth$lene glycol, di-
ethylene glycol and their esters and ethers (tethanes), and also naphthyl
isothiocyanate (Kesscocide).

FALOGETATED ORGANIC COMPOUNDS

Many compounds belcnping to this class find extensive use in pest
control. Examples are carbon tetrachloride, ethylene dichloride, propylene
dichloride, p-dichlorobenzene, and chlororpicrin.

A study of organic fumizants by Roark and Cotton (54) led to the
generalization that iodo-compounds are more toxic than bromo-compounds and
these in turn are more toxic than chloro-conounds. Of several halogenated
compounds that were syrnthesizeH, two were deemed sufficiently insecticidal
to justify patentine them for this use. These two compounds are iodonitro-
brnzne (U. S. patcnt 2,110,1493, L. i?. Smith and Cl~born) and prntaerythrityl
bromide (U. S. pat-Tnt 2,140, 1, Rose- and Haller). These materials are bev
lieved to have great possibilities for insect control.

Halogenated azo compounds have also been patented for insecticidal
use by Vivian and Faller (U. S. patents 2,O95,939; 2,095,940; and 2,095,941).

DII ITROPFEMOL AMT D7 TVATIMES

The hi'gh insecticidal values of dinitrophenol and dinitro-orthocres1l
have been known for some time. In order to lessen their destructive action
on plant foliage, which restricts their use, many derivatives have been
studied. One of thnse contains a cyclohexyl radical in the ertho position.
This compound is now on the market and has been widely us--d. in California
in the form of P dust made by imprecnating walnut-shell fbur. It has proved
effective there for combatin.- the citrus red mite and other insects and,
during 1939, 700,000 pounds of it were applied to 7,000 acres of citrus
orchards.

The Division mf Insecticide Investigations has endeavored tc' make
dinitrophenol and its al' vl derivatives less phytocidal by putting substitu-
ents into the b ydroxyl radical rather than in the ring. The ethers of di-
nitrophenol are covered in U. S. patent 2,115,046 and the esters in U. S.
patent 2,127,090, both issued to L. E. Smith. It is believed that the com-
pounds described in these patents have insecticidal possibilities equal to


- -16 -







17 -

those of the dinitr6phenil derivatives now commercially nvallable. In labo-
ratory tests made by entomologists of the Bureau the methyl ether of dinitro-
o-cresol was very toxic to mosquito lervw'e nnd coaling moth lprvne Pnd the
acetate was toxic to these insects snd also to tobacco hornworms.

AZO COMPOUNDS

Several azo compounds, when tested by cooperating entomologists of
the Bureau, were found to have insecticidal vnlue, snd their use for this
purpose wes protected by g patents issued to Vivian snd Fnller (U. S. pat-
ents 2,094,831; 2,095,939; 2,095,940; 2,095,941: 2,o96,414; 2,110,996;
2,110,g97; 2,111,979), Some of these azo compounIs appnpr rromi.'inp for
the control of codling moth larvae. Accounts of their toxicity to mosquito
larvae have been published by Fink et al. (303, 391).

HETEROCYCLIC COMPOUNDS CONTAINING !'TITROGVN AND/OS SULFUR

Because of the high insecticidal vplue of certain compounds contpin-
ing nitrogen (e.e., hydrogen cyanide, nicotine, nnabasinp) or sulfur (e.g.,
carbon bisulfide, mercaptans, and disulfires) or both nitro;Ten and sulfur
(e.g., thiocyanates and isothiocyanates), attention wns directed. to the
preparation of other compounds of these classes. The correctness of this
reasoning was proved by the results obtaineA by Canpbell, Su1livnn, L. 7.
Smith, and Haller (233) on testin- various synthetic organic comrounds
against mosquito larvae. Twenty-four out of 69 compounds, mostly sulfur
compounds, were found to equal or exceed nicotine in toxicity. For exam-Ole,
diphenylene sulfide killed nearly 100 percent of the larvae in 5 hours at
1:200,000.

A list of organic sulfur compounds used- gs insecticides (250) was
compiled by Roark and Busbey for the benefit of investing ators in this field.
Many of these compounds contain nitrogen also.

Phenothiazine. -- This heterocyclic compound contains both sulfur
and nitrogen and is one of the most promising synthetic organic insecticides
that has been developed in the past 5 years. It was reported by Campbell,
Sullivan, L. 3. Smith, and Haller (233) to be even more toxic thpn rotenone
to mosquito larvae, being very effective at a concentration of 1:1,000,000.
Against codling moth larvae in laboratory tests re-orted by Sieeler, Munper,
and L. F. Smith (261, 295) it was more toxic than lead arsenate. A review
of tests with it against many species of insects was published by T.. P.
Smith (321). An application by L. 13. Smith for a patent on the insecticidal
use of phenothiazine is pending in the United States Patent Office.

All derivatives of phenothiazine so far tested have little or no
toxicity to insects (Schaffer, Hailer, an, Fink, 331) or to gol0fish
(Gersdorff and. Claborn, 399). A method of Pnalyzin commercial phenothia-
zine was described (L. 'T. Smith, 376), anA the ether-insoluble material
which it ordinarily contains was shown to be insecticidally worthless (412).

Phenothioxin (phenoxethiin). -- This organic sulfur compound is re-
lated to phenithiazine, the NH in the latter being replaced by an oVen
atom. In laboratory tests made by several entomologists of the Bureeu,
phenothioxin was as effective Ps rotenone appinst mosquito larvae in All
concentrations up to 1:500,000, and against coiline moth larvae it was more






- i0 ~


effective than lead arsenate. It wat also effective against houseflies
when dissolved in kerosene and used as a sprayr. U. S. patent 2,049,725,
issued to L. E. Smith, covers the use as an insecticide of phenothioxin
and other diaryl thioxins.

Dimethylacridan. -- This nitrogenous compound is also related to
phenothiazine, the sulfur in the latter being replace by the (C 3)2C group.
In labortory tests by Swingle and other entomologists it proved highly
toxic to mosquito larvae, cross-striped cabbage worm, cabbage webworm, and
cabbage looper. Its insecticidal use is protected by U. S. patent 2,099,826
granted Schaffer and Haller. Dimethylacridan is now manufactured on a large
scale for use in the manufacture if rubber goids.

Phenazine. -- This differs from phenothiazine in that the sulfur
atom in the letter has been replaced by another NH. Phenazine looks espe-
ciplly promising as a stomach poison to insects, laborptory tests by Siepler
with codling moth larvae showing it to he more effective thpn lead Prsenate.
Phenpzine and related pyrazines are protected in U. S. patent 2,110,614
granted Vivinn and Haller.

XWnthone. -- This synthetic is related to rhenothioxin, the S in
the letter bpinp replaced by the CO group. It hos bn tested in the l~bo-
rntory by entomologists of the Bureau and found to bd toxic to several
species of insects, including mosquito larvae, celery leaf tier, Muropean
corn borer, cross-striped cabbage worm, melon worm, southern armyworm, and
others. Of especipl interest is its effectiveness arainst codlinp moth
larvae under orchard conditions in the Pacific Northwest. An aprlication
for a Unite! States qptont covering the use of xanthone as an insecticide
has been filed by L. A. Smith

MISCELLAN7OUS 3YNTE7TIC COMPOUNDS

Several hundred organic compounds have been synthesized by the chem-
ists and tested by the entomologists of the Bureau anninst mosouito larvae,
codlinp moth larvae, or other insects. Reports of these tests have been
published by Fink, Sippler, and Munper in cooperation with various chemists
(303, 304, 312, 31, 381: 461).

A method of preparing m-bromophenol and m-iodophenol by hydrolysis
of the acetate obtained b7 the action of acetic acid on the corresponding
diazonium boroflumrides (Waller and Schaffer, 204; L. E. Smith and Haller,
424) was published. This method of rrplacinr the diazo Proup by the acetoxy
group is capable of wide application (L. 1. Smith and Halle-, 207; Claborn
and Haller, 339).

A method of preparing, the drug acetphenetidin from p-aminoacetanilile
was published by Haller in cooperation with Keenan of the Food and Drug
Administration (22d); also a report of the action of isobutylmagnesium
bromide on 3,4,5-trimethoxybenzonitrile (459).

The commercial position in 1938 of synthetic organic compounds used
as insecticides was reviewed by Roark (427). Many synthetics are used as
fumipants (e.p., ethylene oxide, methyl bromide, hydrogen cyanide, paradi-
chlorobenzene), but only a few as contact insecticides (thiocypnates, iso-






thiocypnates# derivptives of &.introphenol and. of cyclohoxyl Rmiine), Ps
stomach insecticides (phr:nothiqziu, or as rkpellents (tetraethyl thlrukm
disulfide). The history and principal uses of those corlpounds wern dis-
cussed briefly.

RELATIONSIP B7T P ff TOXICITY AND CRT-MICAL COTSTITUTION

If the relationship between the chemical. cnnstitutior. and physical
properties of organic compaunds and their to,-icityr to insects were under-
stood, the synthesis of potent insecticides would be a comparatively simple
matter. Unfortunately, organic compounds are highlv sokrcific in their
action on insects, and a material ef"'ective against on species may he in-
effective a/.-inst others. Rotmone, for example, -which is very toxic to
the imported cabbage worm, Pieris rPe L., can be, eaten with impunity by
several species of bore-Y. TLiire is no way of prpdictinc such difference
in behavior, end one cv,not fine. an insecticide suitable for codling" math
control by :neons of tests upon aphids or houseflies, or even upon other
kinds -f lepidpterous larvae.

When different materials are tested upon the ste stage of the sarne
species of insect under identia1 conditions, certain relationships between
toxicity and physical qnd chrcMICIl chrracteristicn are discovered, however,
and~ ~~~~~;tCd thTiiinyfIs" ",
and the Division tf In cid, Investipnti-ns, in cem:raticn with many
entomologists of the Buriau, hnos tk-en a. activP part in the search for
such relationships and has been successful tc so-e dec-ree. Several instan-
ces are given in the section on synthetic organic insecticides.

The problem Penpered zo imortnnt the Division instituteO q funda-
mental investigation of the toxicity of organic compounds in which, because
of thair ease of handling throughout the year, cheppness, and susceptibility
to poisons, goldfish are used as the test animals. A method based on obser-
vation of survival time was de7eloned (70) and te-'ted throuhly in connec-
tion with a study of the photochemical decomposition of rotenone and related
materials (177); very definite relntinships were shown ,among the hydro,
hYdroxy, and acetate derivatives of rotenone (253); all commonly accepted
methods of calculatin comparative toxicities of substances were considered
(g6, 103, 174, 189, 213, 259, 270, 323, 335, 41r), ane a new c'iteraon of
toxicity was developed (257) and used in subsequent work. Realize. that
a fundamental study such as this should: begin with the simpler cor.,uds
a lone-time study of phenol and its derivatives was begun. It has -.en
demonstrated that the replacement of the ox-yren of the phenolic n' :Lus
with sulfur preatlv increases toxicity (323, 415); the irtroductior. of the
nitro proup (460), the chlorine atom, and the bromine atom into phenol
showed that the para derivative is in all cnses the most to: ic, and is
appreciably more toxic than phenol. The fish tests have also been used to
demonstrate the superiority of optically active conpouns over optically
inactive ones, as exemplified by the dihydrodeFuelins (270); and 13o have
been employed in the comparison of nicotine Pnd -nbasine (19) and in the
study of the relationships between phenothiazine and its oxidation products
(393). All the tests with goldfish have been conducted by W. A. Oersdorff,
and most of the publications cited are his.

In '6d6perntive studies to ascertain the relationship between chemical
constitution and toxicity to codling moth larvae a number of hqlopen and
nitro compounds of benzene were investigated by 3iepler, Munger, and L. E.




-20 -


J
Smith (435). Neither fluoro-, chloro-, bromo-, iodo-, or nitrobenzene, nor
the fluoro- or chloronitrobenzenes (ortho, meta, and para) were toxic. Of
the bromo- and iodonitrobenzenes the para derivative was the most toxic.
None of the dihalogenptod (dichloro, dibrono, and diioo) benzenes was toxic,
and of the dinitrobenzenrs the meta isomer is much noro toxic thpn thn other
two. It was concluded that th- data obtained ind soate no marked correlation
between either thp groupinps involved or their relative position with regard
to their toxicity to the codling moth larvae.

INORGANIC IN37CTICIDES

At present the control of injurious insects is largely accomplished
by the applicntion of inorpanic insecticides, and this practice will con-
tinue until suitable or,-nic materials can be developed. Because organic
insecticides are sPecific in their action, whereas inorganic insecticides
such as the Prsenicis are effective against wide ranF of pests, it will
be a long tir'e before the latter are displaced, and so long as they are
used, any information tha-t will lead to a better knowledee of how to use
them is of benefit. The Division of Insecticide Investigations has made
important additions to the fund -f information concernirp many of the In-
organic insecticides, which will be briefly described in the sections that
follow.

The arsenicals continue to be the most important group of inorganic
insecticides, and several of these have been investigated.

LEAD ARSENATE

More than 40 million pounds of this arsenical are used annually in
the United States. The principal advances made in our knowledge of lead
arsenate relate to its distribution on sprayed fruit and its removal there-
from, and are the result of cooperative studies by chemists, entomologists,
and horticulturists. These aspects are discussed in tie section on spray
residues. Certain compatibility studies have been rod-, however, by Murray
concerning its use with ril einiiisions (.I'V and spreaders (154). The rela-
tive efficiency of various spray schedules using lead arsenate has also
been investigated by Steiinor, SazAma, Fnhepr, Pnd Rusk (301). Recently a
survey has been made of all the lead Prsenates on the mnrket with respect
to particle size. A study of the o'-eFti-n -f the use -f lead arsenate in
soils to contr l the Japanese beetle --b led to th discovery by Mell that
greensand marl and limonito both hav -orecticpl r-al1e in counteracting the
phytocidal action of tho arsenic

CALCIUM ARSENATE

Commercial calcium arsenate, of which over 40 million pounds are
used annually for irsecticidpl purposes, is not P simple chemical but a com-
plex and variable mixture. Using a method for determining' free lime in it,
which was developed in 124 by C. M. Smith (Ind. P 1hp. Chem. 1;: 950. 1924),
the Division has made two surveys (Smith and Murray, 91; Nelson and Cassil,
34.4) of all the products on the American market sn( demonstrated that very
great chemical differences exist between nnterials which, by th: ordinary
methods of control analysis, appear identical. A survey of the physical
characteristics of commercial cnlciu arsenstes was made by Goodhue (343)
which gave quantitative data for the first time concerninp the laree differ-









ences in. particle size which exist among, them. "In the course of this work
an. actual chemical.separation was accomplishedIb.v me~ns of a nechonicpl
classifier (Goodhup and Cassil, p6), confirming the complexity m-ntionod
above. A phaset-rule study of the calcium arsenate syeteri by. Nelson of this
Bureau and Haring of the University of Maerylsnd (363) added to our inforri,-
tion on this important insecticide. A new chloroirsenate- f calcium (269)
was prepared by C. M. Smith. A new process for pretarinp calcium arsenate
was developed by means of which the composition can be 7ore definitely con-
tro;lled and the solubility kept low (Nelsin, 452).

The effects of heat treatments of some dplcium arsenrtes on their
toxicity to silkwor~ms -nd bean plants was reported -n by Bulgfr nnd Telson
(474) in 1939.

Four hydrous calcium rrsinntes of tvpicplly different ccmpositibn
were ignited to produce the corresponding anhydrous preparations, end eight
portions of a sample of commercial tetracalcium arsenate were autoclved or
treated with dry hept. A portion of each preparation ws then fed to silt-
worm larvae, ?oribyx mori I. by the sondwich method, -nn4 their toxicity
determined in terms of the median lethal dosage range. Plant tolerance of
these calcium arsenate prepacretions ws determined by n.-rlyine them to bet"
foliage in the greenhouse and estirieting the derre- of foliege destruction.

All the hydrous 'c3lciun rsm ntes were fairly to-ic to silkworm
larvae. Monocalciitm and dicelcium, arsenates were the most toxic anI Pout
equal in toxicity, not%-rithstandinp the frct that the amounts of soluble
arsenic present were greatly different. Tricqlcium end tetrecaIcium arsen-
ates were only about half as toxic as the monocalcium and dicalcium com-
pounds. The anhydrous form of each compound tested was nontoxic to the
extent that, when large doses were fed (12 to 50 times the M. L. D. for
hydrous forms) no, median lethal dosaze range was established.

In general, ignition decreased the pe-rcentape of soluble arsenic
present. However, there does not ar-pear to be any apprecipble correlation
between, the percentage of soluble arsenic Ps determined by the Association
of Official Agricultural Chemists method and the t-xicity to insects or
plants,

Heat treatments of calcium arsa2nate sufficiently severe to mAke the
product relatively safe to bean foliawe likewise himake it nontoxic to silk-
worm larvae. The fact that autoclavihr at 1000 C. for 1 hour does not des-
troy. the toxicity, whereas the srme treatmnt for 3 hours produces a rela-
tiveJly nontoxic tetracplcium ars-npte, surrasts that the toxicity balance
of such a calcium arsenate is rather delicate and indicates that great care
should be exercised in its preparation if the tnxicity is to be maintained.

Dry heating at controlled temrperatures d',es not affect the toxicity
of tricalcium arsenate s? readily as that of tetracalcium arsenate.

PARIS GREEN AITD HOMOLOGS

Paris green is +used: to the extent about 3,0o0,000 to-unds annually.
In 1937 the Division reported a survey of all the preens on the American
market, both Ps to chemical compsiti-n ( earborn, 37T) and pprticle size
distribution (Goodhue and Gooden, 369). The latter constitutee! the first





- 22 -


available information of this kind. Dearborn also discovered that other
acids than acetic acid were capable of forming Complex compounds with copper
arsenite similar to paris green, and methods were developed for producing
such homologs from the lower and higher members 6f the acetic acid series
(260, 295), from the members of the oleic and linoleic acid series (324),
and from the acids contained in various other animal end vegetable oils
(369). Some of these greens have insecticidal power superior to .that of
paris Preen and at the same time are less injurious to plants. Three pat-
ents covering them have been grpnted Dearborn (U. S. patents 2,080,004;
2,lO4,594; 2,127,30).

Reeves of the Bureau of Plant Industry and Yothers and Murray of
this Bureau (466) in 1939 reported that when mixed with vegetable oils and
applied as wound dressings to apple trees to prevent the aphid infestation
that is responsibl.3 for the Prowth of perennial canker, the stearo-, palmito-,
and lauro-arsonites of copper permitted the fungus to advance into tissue
containing a total average of 25r parts per million As203.

OTHER ARSENICALS

Dearborn examined all the brands of magnesium arsenate (71) and of
manganese arsenate (63) on the American market, and compiled the informa-
tion, both chemical and insecticidal, which has been published concerning
these two insecticides (411 and 337, respectively). Magnesium arsenate
was at one time of particular importance as the only recognized means of
controlling the Mexican bean beetle, and the proprietary insecticide
Manganar, promoted as a substitute for lead arsenate, contains manganpse
arsenate.

FLUORI DES

The Division was among the first to recognize the possibility of
finding Fcceptable horticultural insecticides amonr the compoutnds of fluor-
ine, one member having been printed a patent on the subject in l92R (Roark,
U. S. patent 1,524,8894). The possibilities of almost P.11 available fluor-
ine compounds were surveyed, and their insecticidal propertio's called to
the attention of the public (Carter, 55). Newcomer and Carter (201) re-
ported studies of fluorine co~poundr for controlling the codlinp moth.
Special attention was piven to the fluopluminats (68), of which cryolite
is one. The solubilities of numerous fluorides and fluosilicatps were
determined for the first time by Cqrter (22, p7); and the relative toxi-
city as stomach poisons to insects of some of them wns measured by Shepard
and Carter (195). The compatibility of fluosilicates and of cryolite with
arsenical compounds was demonstrated (39), and the incompatibility of all
fluosilicates with lime (97) and of barium fluosilicate with nicotine sul-
fate (157) was pointed out, also by Carter. Two surxeys of the fluorine
compounds on the American market were made (Carter Pnd Roark, 21; Carter,
156), and the attention of entomologists was drnwm by Carter to the fact
that the product commonly called by them calcium fluosilicste is not actual-
ly that (146). A review giving ill avnilable references to the insecticid-
al uses of flucrine compounds wAs prepared by Carter and Busbe (311, 432).
Thre: patents fo' the p.eoaration of insecticidal compounds of fluorine
have been granted Carter (U. S. patents 1,842,443; 18,3,266; 1,863,519).

Because cryolite has become the most important of the fluorine corn-






23 -

pounds used as agricultural insecticides, a special study was made in 1939
of all cryolite materials offered.-for insecticidal use. The fluorine cnn-
tent of 18 samples of cryolite, comprising natural, synthetic (dom-stic -nd
imported), and diluted msteri Is.,,.was determined, Pnd thp euivplont con-
tent of sodium fluoaluminpte c;lculated. Sampleq of domestic synthetic
origin showed an average of 82.8 percent sodium fluopluminpte, spmplte of
foreign synthetic origin ql.3 percent, and samples of natural origin 99.2
percent. Dusting materials showed different sodium fluoaluminate content,
depending on the amount of diluent added.

Solubility determinations were made on all samples by two methcds,.
(1) chemical analysis and (2) evaporation and weighing of the residues.
Results by the two methods were in agreement. The solubilities of the
three classes, synthetic domestic, synthetic imported., and natural, were
very nearly the same and in close agreement with the solubility figure for
cryolite as reported in chemical handbooks (Carter., 4A3).

MERCURIC CHLORIDE

This compound has been used for the control of Pladiolus insects,
in the form of a dilute solution as a dipping bath for the corms. Cassil,
in cooperation with R. Y. Nelson of thr Division of Truck Crop an Garden
Insect Inv-stigations, demonstrated for the first time that the corms ad-
sorb the chemical from solution and thereby reduce the concentration to
about half of that necessary for control, which is of preat importance,
considering the prcticn of using the same solution for several lots of
corms.

COPPER CQMPOUNDS

The compounds of copper are primririly fungicides, but have certain
insecticidal properties as well. Our work hqs resulted in a better under-
standing of the basic sulfates of copper (Nelson, 14), which are the prin-
cipal constituents of bordeaux mixture, and cooperative experiments with
Leukel of the Bureau of Plant Industry showed that amonc all the copper
compounds studied, the basic sulfate, the basic carbonate, .nd compounds
of aniline with copper sulfate and with copper chloride were most, ser-
viceable in controlling stinking smut' of wheat (364).. The copper-aniline
compounds were riven their first trial as fungicides in these experiments.

Commercial copper fungicides, consisting essentially of copper phos-
phate, copper oxychloride, copper zeolite, basic copper sulfate, an; a
copper-zinc compound, were found to affect adversely the toxicity of the
tank-mix nicotine bentonite-soybean oil used successfully in Indiana for
coalinp moth control. These copper compounds alsg p'oduced very serious
foliage injury and reduced the resistance of the nicotine deposits to the
weathering effects of heavy rains (Steiner and Fahey, 451). There is'
great need of fungicides that arepconpati.ble ,ith nicotine bentonite.

SULFUR

Because of the great effect that particle size has on the efficacy
of dusting and sprayine sulfurs, a survey of 44 products typical of those
on the American market was made, and for the first time a clear picture
was given to entomologists .of the areat range of average particle size




- 214--


(ever 10 times) which ma, be endMihtered in insecticidal sulfurs (Goedhue,
396).
MPAY RESIDUS

The Division of Insecticide Investigations has been prominently
identified with the spray-residue problem almost from its beginning in
1925. In that ypar Envland placed an embargo on all apples from the United
States that contained more than 0.01 grain of afsenious oxide per pound.
Control of the codling" moth in the Pacific Northwest required the use of
s :uch lead arsenate spray that the residue at harvest invariably amounted
to more then this, and in'6rder to save the export business in apples
(amounting to 7,099,00 'barrels for the year ending June 1927) it became
necessary to study means of keeping the residues down and of removinp those
which ciuld not be avoid. In lq29 the Division established a field eta-
tion at Yakima, Wash., in conjunction with the Bureau's fruit insect field
station there. Lnter that year the chemical work w;s transferred to Wenat-
chee, Wash,, and in 1935 it was apain placed in Yakima. Work was done with
cooperatinp entomologists to improve sprayinm schedules, and with cooperat-
ing horticulturists of the Bureau -'f Flant Industry to &evelop fruit-washinm
procedures effective in meeting the arsenic tolerance established by the
Department of Aoriculture. When in 1933 the De-patuent established a toler-
ance for lead, it necessitated a renewed strly of lead arsenate residues,
and the establishment of a tolerance for fluorine in 1943 required an ex-
tension of our work to include that element.

Every year thousands of analyses nf washed and unwashed samples of
apples have been made both at Yakima and at Washington, D. C., to determine
the efficacy of various washing, solutions in removing residues of lead ar-
senate. The results of these tests, which were carried on' cooperatively
with Diehl, Ryall, Smith, and Feller of the Bureau of Plant Industry, Beau-
mont Af the University of Marylpnil, Gould of tlh lipst Virdmnias 'Aricultural
Experiment Station, and Newcomer 6f this Bureau, have been'published1n'a
series of articles (32, 39, 72, 1, 193, 1g6, 212, 225, 242, 78, 39 ), and
two patents covering prncesse of washing arsenical residues from apples
have been obtained (Robinson, U. S. patents l,g84,966 and 1,985,100). At-
the same time, the influence of fish oil, mineral oil, and other supplemen-
tary materials upon the magnitude of the residues at harvest were studied
and described in cooperation with Diehl, PRvall, and Haller of the Bureau of
Plant Industry and Beaumont of the University of Maryland (142, 153, 193,
252).
The effect of apple growth and of weathering in altering deposits of
leaedarsenate throughout the prowinp sehscn was determined by Carter and
Newcomer (196).

Experiments were undertaken in southern Indiana'by Fahey in l935 and
1936, in cooperation with Steiner and associates of the Division of Fruit
Insect Investirations, to determine the extent of decomposition of lead
arsenate spray residues on apples as measured by their ratios of lead to
arsenious oxide. The residues were analyzed immediately after the various
cover-spray applications and again after the residues had weathered. A
t~tnl of 249 samples of Apples an Apple foliate were used. The'vrare
rptin of lead to areenious oxide in these samples did not vary significantly
from that in the Nririnal spray material, and samples taken immediately
after spraying showed no significant difference from those taken after
weathering. The slight variations between the ratios are in reality the





25 -

combined analytical errors of the methods of residue analysis. The high
ratios obtained by early investigators are due, probably, to inadequpte
samples or to unreliable methods of analysis (431).

In cooperation with Hellor of the 'Threau of Plant Industr7 and Gould
of the West Virginia, Agriculturrl F-inri'wzat Station, t,! variability of
residues of lead arsenstp within individual spray trptr.ntr wns investi-
rated (40, 325, 359) in order to determine the rrocedvre- necessary to ob-
tain adeauate samples in all investitTational work. As the result of co-
operative work with Wichmann and associates of the Food and Dru, Adminis-
tration, improvements have been made in the annlyticnl rrocedire for lead
(208). Methods for the determination of arsenic (49, 49, 16g, 196, also
unpublished recent work) have also been in"roved.

Parallel with the work on residues of lepi Prsenate, similar studies
have been carried out by Carter on fllcride resid-.es, moctl7V residues of
cryolite on apples (159, 226, 2r7), Pnd three pstmits covering new washing
solutions especially adapted fo- cryolito rcmoval were &rsnted to him
(U. S. patents 2,046,546; 2,C *6.547; 2,o46,54g).

The Division his continually kept In r"nO the necessity of studying
residues of other materials for which no tolerances have been established.
In this work the methods to be used in deterriinin7 the resieues hav had to
be developed, as described. in tre section on azaltical inve stations.
The influence of the characteristics of oil emulsions upon the aaorunts of
oil deposited was shown by studyvring, the oil residues (Cressman and Dnwsy,
224); the removal of nicotine bentonite residues from apples hns been shown
tm be easily accomplished (Fahey, Ruzsk, Steiner, and Sazrma, 407); and the
presence of lead Pnd arsenic in various forms of tobacco, and of arienic in
the smoke therefrom, hns been studied (209, 30,). An e~hpustive study
awaitingp publication) of the derris reside uos on cabbape has been mado,*.-iving
the only data available on this important P'bject. The entomolop.ists of
the Bureau hnve been riven the results of o-!,.- tdzenrmira.tions of residues of
phenothiazine on cherries, sulfur on citrus, tartar ertic on citrus, borax
on rice, etc. all of which are of rpreav inortance to them in shaping" their
spraying and dustinp programs. A study by Murray qnd Ral ( 4.4), reported
in June 1939, showed tht phcnothir~zino sprny residues on apples in Amounts
up to 0.060 -rain *er polnd npr be rcr1dily reduced to O.1 g-rain per pound
or less with present washin equiiprient and solutions (e.g., 1.5 percent HCl
at 1100 F. for 30 seconds).

A method was described for sprrying paraffin-coated mica plates with
oil emulsions and determining the nuantitins of o.1 deposited by difference
in weight (Dawsey, Cressman, and Filey, 330). Co mparson between the qian-
tities of oil deposited on the paraffin suorfaces of the plates and those
deposited on-chrysanthern-am foliage, a.s determined by chemical analysis,
showed that various enmulsions give different rstios of plant d:cposit to
plate deposit. It is, therefore, not practical to attelipt to standardize
the sprays intended for the plant surface against the plate surface.

The development by Dawsey snd. coworkers of Analytical methods for
accurately determining residues of petroleum oils on leaves (11, 292, 371)
enabled studies to be made of the relation between oil deposit and insecti-
cidal efficacy (Cressman and Dawsey, 259). The compnrativi insecticidal
values of three petroleun oils with 6, 1e, and 33 percent by volume, re-






spectively, of sulfonatable material were investipgated in laboratory and
fiel1 sprayving tests. The oils were Pnplied, in the form of emulsions con-
taininz front 0"9 to 2 percent of oil, sodium oleate soap being used as the
emulsifier, to calihor-trea plants and trees infested with the camphor
scale. The other characteristics of the different oils were substantially
the same, so any detectable differences in scale mortlity could be due
only to differences in the sulfonatable portions. When sprays which gave
ecuel nil deposit were compared, the variations in mortality appeared to
be entirely random, and no differences were found which could be attributed
to th? sulfonatable content of the oils. Analysis of the oil deposits left
by sprays showed that substantially equivalent deposits were obtained when
eaual concentratiors of the different oils were applied. In the laboratory
tests the oil deposits produced were indeprndant of the sulfonatable con-
tent of the oil but varied directly with the oil content of the spray.

The chemc-_il methods of stuedyinr codling moth insecticides at Vin-
cennes, Ind., were described in 1939 under the title "A field method for
the chemical evolution of spray deposits resulting from the application of
insecticides for control of the codlIne moth" by Fahey and Rask (.7l). The
methods of samplin: tin chemical anal-sis are described for residues of
lead, arsenic, nicotine, -nd phenothiazine. The wenthe-inp of residue de-
posits and the reltionslnip of re-idurs t, area of fruit are discussed.

Fa'ey, Rusk, gteiner, and 3azvna (475) in 103q reported mn the ease
of residue removal from late and early sprayv applications of lead arsenate
to a.ples. Spra sched'-.les desi-ned to permit such P comparison were Pp-
plied in experience l apple orchards near Vincennes, Ind. Samples of fruit
from the sprayed 'L os were washed with hydrochloric acid solutions, and
analyses were made for lead residues before and after washing.

The residue load at harvest from a riven number of leAd arsen.te
cprnys increases as the time of spray application appronchpF harvest time;
thus, a final cover spray of leod arsenate my lepvo, at harv-st, a residue
load eaunil to that rasultinp from four first-brood sprays. The residues
from sproys applied in the second-brood 7reriod Pre more easily removed by
wshin than are residues from the sarme number of the same sprays applied
during the first-brood Derind. The use of oil Pdhesives with organic in-
secticides, in second-brood sprays, mikes the residue of lepd Prsenate from
firt-brood sprays As difficult to remove as Are residues from lead nrsenpte
used throughout the season.

A digest of the literature through 1 :34 relptire to insecticidal
spray residues (431) was issuel by Busbey enrly in 1939.

FTMIGANTS

From its creation in 1q27, the Division of In-ecticide Investiga-
tions has been active in the study of fumixunts. In cooperation with ento-
mologists, it tested several hundred organic compounds (Roark and Cotton,
54) in an endea ror tn finld substitutes for the dangerously inflammable and
erolosive carbon disulfide. As a result several new fumigants now in com-
mercial use were discovered, such as methyl and ethyl formates (9), ethylene
dichloriie (2), ropylene dichloride (6), and ethylene oyide (16). These
are discussed below in detail. The high insecticidal value of the vapors
Af other compnnds was also discovered, for example, those of chloroscetates


- 26-








(U. S. patent 1,799,3,22) and other halogenated fatty esters (11). These
discoveries were all made jointly with R. T. Cotton.

The use of carbon dioxide to increase the insecticidal efficacy of
fumigants wac discovered by Cotton and Younp (30), and mixtures of carbon
dioxide with ethylene o'-ide and with methyl fo-rmate havr, been marketed for
use as fumiigants. Back, Cotton, Young and Cox (64) described tho use of
the ethylene oxide-carbon dioxide mixture for treating stored grain.

In cooperation with the Division of Fruit Insect Investigations many
organic compounds were tested for toxicity upon the California red scale
(Cupples, Yust, and Filey, 29g) in mi effort to find substitutes for hydro-
gen cyanide. Methyl thiocyansate kLathrop, Cupples, Filey, and Yust, 2g4)
proved toxic to the scale but wes also injurious to citrus trees. The
"interval shooting" or piecemeal application of hydrogen cyanide in citrus
orchards wasdiscussed (Cuppler, 172), Pnd the latest developments in the
fumigation of mushroom houses with sulfur dioxide (Davis and Young, 216,
246) and with hydrogen cyanide (Davis and Claborn, 272) were described.

The fumigation of cereal products, flour, and flour mills with
hydrogen cyanide and other fu;iigants was described (Cotton, Waner, and
Young, 273, 294, 309, 336, 361); deficiency of o-v n as a factor in kill-
ing insects in vacuum funigation was dicussed (346); ind the use of
heavier-than-air fumigants on insect-infested prain Pnd other products
was reported on (359). These studiis were iriade by Cotton, Wqgner, end
Young at Manhattan, Kans. Tha rate of evolution of hydrogen cyanide from
calcium cyanide was studied (37). The effect of a number of fumigants on
the termination of seeds was investigated by Young and Roark (45, 54);

Many studies of the vaoor pressures of fumigants were made by TNelson
and Young (23, 24, 27, 73, 1g5), and inroved nparatus for mepsuarinp par-
tial vapor pressures of binary liquid systems was perfected by Nelson (135).
From these data were calculateO the maximun weights of various fum* ants
which can exist in vapor form in a 1,000-cubic-f,-rt fmigatinF chamber (2q),
which were published by INelson and Roprk, who ascompiler' data n the
densities Df mixtures of air and various fumigents (94).

Methods were devised for determining small quantities of methyl bro-
mide in air (Busbey and Drake, 4)), and for determininp hvdropen cyanide
in a mixture of air and carbon dioxide (Cupples, 167). Apparatus for the
rapil vaporization of carbon disulfide (Weigel, Young, and Swenson, 4), for
burning sulfur for mushroom house fumigation (Davis and Young, 237), for
laboratory fumigations with hydr-,pen cyanide under controlled temperature
and humidity (Cupples, 166), and for fumieptinp Prhids under laboratory
conditions with minute ounntities of nicotine (F. TT. Richardson and Busbey,
350) was devised and described. The binary system cprbon tetrachloride-
ethylene dichloride which is used as a fumipnnt (2) was studied, and the
boiling points and specific gravities were recorded. as aids in analysis
(Young and Nelson, 129).

The work of investigators of fumigants has been aided by the publi-
cation of bibliographies of some of the more important materials, for exam-
ple, those on chloropicrin by Roark, Gersdorff, and Busbey (79, 2oq, 253),
that on ethylene dichloride by Gersdorff (132), that on ethylene oxide by
Young and Busbey (247), and those on cyanides by Cupples, Young, and Busbey








(R,8,S, 47o, *76). QX a~tidle6 and, re riews of rpro. iti.
f'mniants have also been published'by Roark (5, 101 57, 105, I;, 110, 114*,
21S, end 293)

The volume of popcorn was found to be affected. by certain fumipints
use! to treat the corn when newly harvsted for' the destruction. of insects.
Pinicatinr the corn with hydrocyanic acid i' ipovod Its popping qualit7,
carbon disulfide and ethylene oxiee at regular dosages had little effect,
whereas carbon tetrachloridq, ethylene chloride, and chloropicrin had ad-
verse effects. In all cases at the end of 30 days the deleterious e ffect ts
ha completely disappeared and the volume of the popped samples was apain
at normal (Young, Cotton and Wap-.'er, 429).

FOXMATiS

The hih insocticidal value of the volatile sters of formic acid
was disc'verel by this Division worl.'in- in c-operation with the entomologist
R. T. Cotton (g, 54). Methyl formate ,and ethy l formate have come into com-
mercial use for the fumigatinn of raisins, dried fruits, nuts, and other
foodst iffs and. also stored tobacco nrd other commodities. A mixture of
methyl fQrnate 4n6 carbon n dioxide has been used co=.Percinlly also. The vs-
po-r pressures of the foroiates were eeternined (24), Pnd from these data were
calculuted the maximum weights :.f the various formates that cn exist, in
vppor fnrm in a l,0O0-cubic-f-ot futniptin, chamber (20). Thi s information
is helpful to the prpctic,'l funiatcr.

ETHYLEN, DICVLORID" AND ?ROPYLE7 DICIPORIDM

The value of these two organic solvents as insecticidal fumignts
was reported (Ctton and Roark, 2, 6, 014). In order t- reduce the slight
fire hazard of ethylene dichl,ride, it is mixed with one-third' its volume
of carbon tetrachl-ride (2),. Thth ethylene dichloride and propylene dl-,
chloride are now widely used f')r killing weevils in rrain and clothes moth
in furs and woolen clothing. These fumigants are now used in, place ,f cold
storsee by many warehouses storing furs, clothing, and ho usehold goods be-
cause their use is cheaper and more effective in killin_ insects. They are
inexpensive costing ahout 5. or 6 cents .1er pound), readil available, rela-
tivrly n"-nto-ic to ran, and leave no "bjectionnble odor in fU.rigated arti-
cles, A physico-chmical study of mixtures of ethylene dlchlbride and car-
bon t:trachlorid, wns made and the-ir bniline prints nnd spe-cific prAvities
were recorded as aids in analysis (129). A comprehensive biblioprpp hy of
ethylene' aichoride complete through 1030 was riblished (132).

ETFYLEIT, OXIDT

This fumigant is now widely used for destroying insect life in all
kinds -'f stored products, especially packafred cereals, bagged rice, tobacco,
clthinp, and furs. Tt is best employed in vacuum fumigation chambers. .
Ethylene oxide is also used for destroying insects ihfestinp books and pa-
pers. The Federal Archivfs Building in Washinvtn, D. C., in which are
stored pricleoss historical docirments, is equipped with vacuum fumigation
apparatus ih which ethylene oxide is used to treat Insect-infested material.
A recent use of ethylene oxide is, to destroy m,)lds, fungi, and other plant
life infesting spices, especially packaged spices. ',thvlene oxide is the
material par' excellence for this purposee because it is highly effective at


_ 2g_






29 -

an economical dosage and leaves no odor, flavor, or deleterious residue in
the fumigated product. The use of ethylene o~ile for-combatin economically
.injurious funki as well as insects is covered by-U. S. patent 1,791,429
granted Roark and Cotton. The use as a-fumigant of the mixture of ethylene
oxide -with carbon dioxide is also protected (Cotton and Young, U. S. patent
2,024,027). These inventions are the result of cooperative research by
chemists and entomologists and are more fully described in reports by Cotton
and Roark (16, 54) and by Pack et al. (64). A bibliography on the use of
ethylene oxide for pest control was published (247).

CHLOROPICRIN

This compound, which was Pxtpnsively used as a tear gas in the World
War, has valuable insecticidal, fun,'icidal, and bactericidal properties.
It is free from the fire and explosion hazards of carbon disulfide and other
fumigantsand, because of this and other desirable propertiPF, it has come
into extensive commercial use for the fumigation of grain, ships' holds,
and warehouses, and injurious insects, nematodes, and micro-organisms in
soil. We have directly stimulated the use of chloropicrin by issuing three
bibliographies (79, 209, 253) on the subject. These contain abstracts of
many publications unavailable to most scientific workers, such as works
written in Russian.

HYDROGEN CYANIDE

This fumigant continued to be the most important of all. In spite
of a history of- use of 50 years, there are many problems connected with its
application against specific pests that require study. At Whittier, Calif.,
the Division of Insecticide Investigations, in cooperation with entomolo-
gists of the Division of Fruit Insect Investigations, has carried on chemi-
cal investigations since 1930 on the fumigation of the California red scale
with hydrogen cyanide.

Experimental field fumigation investigations added to our knowledge
of the concentrations of hydrogen cyanide in tents during regular commer-
cial treatments and provideO dosare dats for comparison with insect mor-
talities in-seasonal fumigation studies.' The multiplicity of variables in
field experimentation, many of which were not amenable to control, coupled
with the impossibility of reproducing results, made the identification and
evaluation of the factors responsible for wide variation in the insect mor-
tality practically impossible, and ultimately led to the postponement of
field w~rk of this nature in favor of laboratory investigations. Fowever,
the study of field fumigation yielded data from which a mathematical for-
mula was develo-oed that expresses the drop in hydrogen cyanide concentra-
tion with time under a fumigation tent. From a practical standpoint the
results show that the use of a more nearly eas-tipht tent and thorough
mixing of hydrogen cyanide with tho air under the tent will assure better
insect kill.

For the laboratory studies of hydrogen cyanide fumigation P special
apparatus was devised and constructed. By means of this it is possible to
control temperature, humidity, and hydroen cyanide concentration and to
expose the insects to the fumigant at once, thus avoiding the effects of-
protective stupefaction. Reports of these studies are being prepared for
publication.




-30 -


CHLORU~t

The control of stinking smut of wheat, oats, barley and sorghums bv
the -application of gaseous chlorine was investigated by Leukel (473) of the
Bureau of Plant Industry and Nelson of this Bureau. Chlorine gas is capable
of killing smut spores of grains under carefully controlled conditions but
offers greater promise in controlling fungi on garden seeds.

ACCESSORY MATERIALS

It is comparatively seldom that an insecticidal material is used
alone. Dusting materials are commonly mixed with inert powders to aid in
their distribution, and spraying materials frequently have added to them
wetting and adhesive agents to improve their application and adherence to
fruit and foliage. A clear understanding of the roles played by these
supplementary materials is essential to the proper conduct of chemical con-
trol of insects, and the Division has, therefore, devoted condiderable
attention to them and has made worthwhile advances in our knowledge of them.

WETTERS AND SPREADIRS

Cupples has developed a quick and easy method of determining the
spreading power of solutions over a standard oily surface (266), and by its
means has made a detailed study of the spreading ability of sodium oleate
(266, 275), of potassium and ammonium oleates (293), and of the sodium salts
of numerous other fatty acids (349, 472), as well as of triethanolamine
oleate (379). A survey of the chemical nature of certain spreaders used
with lead arsenate was made (154), and a comprehensive list of the more
modern wetting agents, includinp- measurements of their spreading coeffi-
cients, was published by him (393). The relation of wetting power to abil-
ity of liquids to penetrate wood anA the relation of initial spray reten-
tion to spreading power have been studied. Among the solid, powdered sup-
plementary materials, bentonit,a has been given special attention, and the
role which it plays in the formation of nicotine bentonite and other salts
with organic bases and alkaloids was explained for the first time by C. R.
Smith (222).

In a study by Cupples (46g) of inorganic salts as adjuvants for in-
creasinp the wetting power of a proprietary wettine agent ( a sulfonated
ester of a dicarboxylic acid) it was found that no precipitation occurred
in the presence of large amounts of cplcium or magnesium. Additions of
chlorides of calcium, magnesium, or sodium to solutions of this wetting
agent produced significant increases in wetting powers, as measured by sur-
face tension or by spreading coefficient on mineral oil. The improvement
is so substantial as to indicate that this effect may be of practical im-
portance in the formulation and use of these materials.

An investigation by Cupples (472) of the wetting and spreading
properties' of aqueous solutions containing mixtures of sodium carbonate
with n-caproic, n-caprylic, n-cqpric, lauric, myristic, and palmitic acids
led to the conclusion that for aqueous mixtures of sodium carbonate with a
series of fatty acids at P concentration of 1.0 percent of fatty acid, the
surface tension, interfacial tension against mineral oil, and spreading
coefficient, when plotted as functions of the alkali-fatty acid mole ratio,
give curves which are similar in form with few exceptions. The relative









positions of the curves correspond anproximatelv with the nrder of increas-
ing molecular weight of the fatty acids.

The characteristics of the carbonate mixture are similar to those of
the corresponding hydroxide mixtures, with some differences which are nppnr-
ently accounted for by the diacidic nature of the carbonate. Th olecte
mixtures have exceptional properties which help to explain their excellence
as detergents.

DILUENTS

A comprehensive study of the physical characteristics of 6ilunnts
suitable for use in making dusting mixtures is under way at present.

STI CKERS

The effects of the use of fish oil and mineral oil as adhesives with
lead arsenate upon the magnitude of the deposits obtained was investigated
by us in cooperation with Diehl (142) and Ryall (153) of the Bureau of
Plant Industry.

A new adhesive especially adapted for causing derris powder and simi-
lar organic materials to stick to foliage was invented by Goodhue (U. S.
patent 2,129,517). This consists of rosin residue or pine oil fcots, a
substance that remains in the frPctionatinz column after the removal of
solvent and nine oil in the steam and solvent process for the rrofuction
of navql store products from pine wood. This adhesive is b st handled when
emulsified in water with ammonium caseinate. It is noniniurious to foliage,
does not accelerate the decomposition of rotenone and related compounds,
and retains 85 to 95 percent of the derris on bean folipe after a washing
test equal to 2-1/2 inches of rain in a period of 9 minutes. The concen-
trated emi1sion is comnr.rciallv available and is widely usea, especially
for combptinp the Japaiiese beetle with derris.

Additional stickers that have been developed by us are the reaction
product ofl fu-fural with Pniline (GoOehu, U. S. patent 2,146,257) nd. the
reaction product of furfural with acetone (Goodhue, U. 3. patent 2,146,25g).

EMULS I FIBERS

A formula for the preparation of insecticidal oil emulsions using
casein rirnir as the ePmulsiyin- agent w.s developed by Newcomer qnd Car-
ter (191j). '2lvions na.d in this wa, h-ve been thoroughly tested in the
laborcr-cv c i in the orchard, and s own to be rr-icticpl, ecenomicFl, and
effective, and fruit growers in the 7-cific Yorthwcest are us ni them suc-
cessfully on a large scale. The influence of various emulsifiers on the
quantity of oil deposited from emulsions was determined by Cressman and
Dawsey (224).

ANALYTICAL IN1VST IGATIONS

The Division of Insecticide Investigations, in the course of its
developmental work, is constantly concerned with the improvement of exist-
ine methods of analysis and the development of new methods when none are
available. This has led to some notable contributions theft have been of





- 2 -


great use to every one interested in insecticides.

Because of the importance of arsenic as an economic insect poison,
analytical methods for its determination and for the examination of insecti-
cides and foodstuffs containing it are extremely important. The Division
has always taken a leading part in this work, some one of its mambors having
acted for years as the Referee on Arsenic for the Avsociation of Official
Arriculturi.l Chemists, conducting the collaborptiv- work for th: Associa-
tion and submitting regaler annual reports (2-1, 333, 390, 444). Numerous
important improvements have been made by us in the Gutzeit method of deter-
mininr the micro-amounts of arsenic that are encountered in spray-residue
work. Improved methods for the preliminary digestion of the- sales have
been worked out by Barnes (49), thp accuracy of the method has been deter-
mined by him and Murray (49), end means of overcoming certain interferences
hare been worked out by Gross and Cssil (i69, lq 339). Recently, in co-
operation with Wichmann of the Food and 71rur Administtration, a new method
(446) for micro-aoounts of arsenic has been devised by Cossil, which is
equally as speedy as the Gutzeit netbo,l and far 7o-e precise. A procedure
wns published for detorrining arsenic in soil treated ,,ith acid lead arsen-
ate (Koblitsky, 45?).

The Divisi-n -has also developed a method for free lime in calcium
arsenate that has been the most imprtnnt factor in unravellinp the make-up
of this most complex insecticide (91). Recently, tartar emetic has assumed
some importance -t an insecticide, and because of the lack of a suitable
method for the determinati-'n of snti~nony in s-ra residues fr-m its use, a
naw method was develope d in cooperation with Devidsn anl, Pulley of th: Bu-
reau of Agricultural Chemistir nnd. Vngtneering (301). Advances have been
made in the analysis of foodstuffs for lead (Wichmpnn et al., 2O), and a
specific method was worked out for lead in chewing tobacco and snuff (Cpssil
and C. M. Smith, 305). A method w.s develop& for residues of barium fluo-
silicate (Carter, 102) anr -ther fluorine compounds (Carter, 354), and for
the copper, arsenic, zinc, mercury, and fluorine (Carter, Capen and Cassil,
403) left in wood that has been imprearnated with their soluble salts.

The study of natural insecticides of plant origin has resulted in
.the .development and publication of methods for nearly all the important
compounds of this class. The Division has been the pioneer in respect to
methods of examining rt ,none-bearing, plants. The discovery by Jones that
rotenone forms sparingly soluble comy lexes with carbon tetrachloride and
dichloroacetic acid led to tho development of a Pmac-'- math6d (122, 165, 334,
423) for the estimation of rotenone in rots. In c-oeration with Graham
(373, 377) of thQ Food an Drug Ad'iinstration, who also is Referee on In-
secticides for the Association of Official Arricultural Chemists, the
method was further improved and has been rractical!7 universally adopted;
the Food and Drug Administration now uses it in control work, and the Asso-
ciation rof Official A-ricultural Chemists has taken action to make it an
official method. One qualitative color test was aevelopel (Jones and C. M.
Smith, l69 which permits a rapid testing in the field during search for
rotenone-boaring plants, Pnd such use has Pct'iilly been made of it in the
researches of the Dernrtient as well as elsewhere. Another color test for
micro amounts of rotonone any de.ielin was devised by Gross, Smith, anl
Godhue (219, 276) which permits of quantitative arplication, and. this test
has been used by numerous investigators all over the worll as a ouick means
of studying the lecomposition cf eerris and the isolation of constituents







A4 33 -

fYkom it. Recently aconp4rAson he h maee -of "Il published color tests.
The pes~ibility thatopti.c%:l rotation of- the extracts might serve for test-
ing roten)ne-bearing plpnt -wa looked. into by Jones (322). In cooperation
:with Sullivan, chemicsl meanseof sti.mnting the insecticidal efficacy of
derris Ar cube (299i 395) were developed by Jones and Smith which are defi-
nitely of service. in eomparine various samples.

The methods now used for the determination of the two active princi-
ples in pyrethrum powder are not wholly satisfactory. We have contributed
a new procedure for estimating pyrethrin II (Haller and Acree, 263) and at
present have under study another entoir:ly new procedure for estimating both
pyrethrins I and II separately.

Our contributions to the analysis of nicotine products have been
particularly notable. One micro method, suitable for fumigation concentra-
tions, based on weighing the silicotunestate compound (Spies, 317, 320),
and another based on the photoelectric estimation of the same precipitate
(Goodhue, 374), were worked out. Two methods specifically adapted for
determining nicotine in spray residues were developed (Markwood, 379, 445),
the latter colorimetric procedure permitting the determination of the mi-
nute quantity of nicotine spray residue on one apple.

The attempt tq develop rvnthetic organic insecticides has also le&
to numerous important advances in analytical technic. The examination of
one of the fumigants developed by the TBureau, namely, the mixture of ethyl-
ene dichloride and carbon tetrachiloride, was facilitated by ,the determina-
tion of the boiling points and specific gravities of all mixtures of the
two components (Young and Nelson, 129). The sturly of fumigation problems
was ald-ed by a ncw method of determining hydrocyanic acid (Cupples, 1,7);
a method for the macro-examination.nf phen-thiazine was devPloped (I. E.
Smith, 376); as well as a micro-colirimetric urocedure (not yet published)
suitable for the determination of the c-mpound in spray residues; the in-
cresing usp of mcthvl bromide led to a mnth.'A for its estimantion in air
in the small concentrations encountered in fumigation (Busbey and Drae,
400); and our studies of sprayr oils led to definite advances by Dawsey in
methods of deteriininp the deposits from oil emulsions (161, 292, 371) and
of examining the oils for volatility (lg).

The study of natural insecticides ,f plant )ripin and of synthetic
organic insecticides has led to several improvements in micro and semi-
micro methods of organic analysis. Improvements have been made by Clark
in the procedures for determining carbon and hydrogen (197), nitrogen (203),
halogens (227), sulfur (262)i acetyl (316, 362), methoxyl and ethoxyl (131,
467), and a general article on micrn analytical methods was presented be-
fore the Association -f Official Agricultural Chemists by him (1g2), the
present referee on that subject for this ass-ciation.

Physical methods of analysis have also been given attention, and a
new sedimentation meth-d for the measurement cf the particle-size distri-
bution in insecticidal materials was developed (Goodhue and C. M. Smith,
315). The sedimentation and micro projection methods for determining the
particle-size distribution of insecticides were compared, using three com-
mercial samples of-dustinp sulfur. As far as precision is concerned, there
is probably no choice-between the methods, but the sedimentation method is
less time-consuming (Goodhue and G,oden, 440). I3PAR







34 -

A process for the recovery of' silver .and_ iodine from silver ifdide
wag w,)rked out and patented (Spies, 241 and U.. ..39atent 2,QO,539). In.
cooperation with Hillig of the Food and. Drur Administratipnr, Clark (h1i,
417) worked out a chemical procedure for evalTatine spoilage in canned. fish,
especially salmon and tuna fish, using the improved apparatus and modified
Dyer method ti which reference has been made elsewhere. Directions were
published by Clark for an improved- method for the preparation of lydriodic
acid suitable for alk-oxyl and Friedrich-Kjeldahl nitropen determinations_.
(422).

The effect of particle size on the toxicity.of calcim arsenate,
paris preen, synthetic cryolite, phenothiazine, and acid lead. arsenate to
the codling. moth.larva was studied by Goodhue in.ocooperation.with.iepler
(4,37). Coarse phenothiazine particless having a midsize o 1+5 microns) wns
much less toxic than was the.medium (15-micron) or fine (4-microzj) fraction.
No great difference in toxicity of the different fractions wqs obtained with
the other insecticides, .

.APPLICATION OF STATI3TICAL MVTHODS TO I11sECTICIDE PROB;EMS ..

Much of the work on developing, testing, and establishing the commer-
cil4-value of insecticides is necessarily ofthe variable natvre which can
be- evaluated only by the application of the theory of probpbilities. This
is particularly true in the stu..v of srray derosits and.their rmoval by
washing or other meqns, for the aT-plicstion of srrays i far from an exact
procedure, the sprays are deposited on frait withit$ natural large hetero-
geneity, and the nature of the washing technic.employed is not,,aduratglv
standardized. Further,, in Pll tests against insects no amount Qf refine-
ment in the mechanics of testing will overcome pthe inherent variations_ ,n
suscertibilit, of individual insects,.pnd recourse miipt bp had to the st-..
tistical study of average effects. -.

The Division h,-s long annreciated this situation and hes continually
striven to rromote the.statistical viewpoint in relation to insecticide
problems: numerous publications have been issued calling the attention of,
other workers to the conclusions to be drawn from researches Qprried on in
the Division.

Barnes (26) studied the distribution of arsenic residue.on a larep,
number of apples sprayed with lead arsenste, anplyzing individual apples,
and by the application of statistical considerations arrived at an estimate
of the number of apples that must be used to insure adequate sampling..
Barnes and Murray (40-) extended this work to include washed apples, and
again defined the size of representative samples. The results were ob-
tained by the Gutzoit method, the variance of which was also determined by
Barnes and Murray (4S). Later, when methods of determining lead residues
were developed to the point where their accuracy far exceeded that of the
Gutzeit method, other, lots of unwashed and washed apples were studied by
Smith and Cassil (359) with regard to distribution and standard deviation
of deposit, Pnd still better estimates were arrived at regarding suitable
sampling technic. These findings were then put into practice, so that
Haller, Cassil, and Gould (325) were guided entirely by statistical con-
sideratimns in estimating the variability of lead residues between trees
in a plot, and the same authors together with Murray and Beaumont (399)
critically judged their results of residue-removal studies on eastern




-35 -

apples. Without the statistical ba kgrounO Fahey Pn Rusk (43q) could not
have intelligently interpreted their fin ding that the rntio between land
.and arsenic in residues from lead arsenate does not change appreciably with
time, and would not have been able definitely to show the variaility of
residues from part to part of an apple and from top to bottom of a tree
(471). The statistical method has been cairied by 7pirs (320) and Cassil
and Wichmann (446) into oar work on analvtical m tboA.. It also played an
important pprt in some rec-nt work (still iunpublished) by Cassil on sur-
vey of derris residues on cabbage, rnd in nn investigation (Plso still un-
published) by McGovrPn and Cassil of thp relation bptwren the insecticial
potency of ppris green and its degree of comminution.

N",W AND IjP'qOV7*D APPqAT7S

Accomplishments of the Division of Insecticide Investigations under
this hearing: include the develo'uent, in cooperation with entoiolorists, of
an improved apparatus for the rqpid vwpori7sation of carbon 9isulfide (Weigel,
Yourg, and Swenson, 4) an. an 1mTprovct burner for sulfur inten'd4 especially
for mushroom-house fumigation with sulfur dioxide (Dpvis and Young, 237).
Carbon disulfide is one of the m-st potent fumirants used for killing
weevils in stored grains and cereals. The annual loss caused by these and
other insects attacking these products is about iA t ,OO',00. Carbon di-
sulfide is also used for treating soil in greenhouses and for destroying
Japanese beetle grubs in soil surrourAing the rocts of rurs-ry stock. Sv-
eral species of mushroom flies, manure flies, ruvhroom mites, and sprin.-
tails cause an estimated annual reduction of about 20 percent in the roten-
tial vqlue of the mushroom crop produced by commercial growers. This
direct loss amounts to Pbout $2,000,000 P year. One of the effective means
of combating these pests is fumigation with sulfur AioxiiP. The develop-
ment of improved means for applying these valuable fumigants assists in the
fight against destructive pests.

In order accurately to study the effect of a fumigart upon a eiven
insect, it is necessary to control very clopely both the temperature and
humidity. An improved eouipmcnt for laboratorv funigations i.ith hydrocyanic
acid which enables the operator to do this was developed nd described
(166). Special apparatus for stu ying the effect of a minute nuantity of
nicotine vapor upon aphids was devised (3rO) by Pusbey in cooperation with
H. H. Richardson. In the study of fumigants it is important to -now their
vapor pressures, because from these data cen be calculpted the amount of
any fumigant necessary to saturate the atmosphere in a given space. An
apparatus for measuring partial vapor pressures of binary systems was des-
cribed by Nelson (135).

A new mechanical duster for applying insecticidal dusts was devised
and patented by Goodhue (U. S. oTatent 2,114,0q2). The efficiency of an in-
secticide depends largely upon how thoroughly it is a-tli id, and this new
dusting device will enable the operator to apply nicotine dust and other
dusts more effectively. Goodhue and Siegler (3 7) developed a notor-driven
telescoping stirrer for use with an insecticide-sprnyin ap-aratus.

Many devices helpful to the chemist in his laboratory operations
were invented or imnrroved. These include an electrically heated spnd bath
(Clark, 199), a funnel-heating device (Marl-wood, U. S. patent 2,135,551 Pnd
455); a differential-pressure control mechanism for vacuum distillation





- 36 -


which wa3 developed by Palkin of the Bureau of Agricultural Chemistry and
Enpineering and Nelson of this Pureau (230); a-new constant-temperature
bath for heating vacuum stills (Nelson and Haller, 353); a sensitive thermo-
regulat-r for controlling the temperature of constant-temperature baths
(Goodhue, 308 and U. S. patent 2,095,738); an improved melting-point appars-
tus (Schechter and Hqlltr, 4O!); a lnborptory spr-ying And wn.shing Arpara-
tus (Chisholm, 40); and improved forms of apparatus for the determination
of m(thoxyl groups (Clark, 131), for the identification of volatile fqstty
acids (Clark and Fillip, 416), fmr the determination of *mol-cular weights
(Spies, 162), and for collecting cigar smoke in order that its arsenic
content mav be determined (Gross and Nelson, 205).

In working with insecticides of plant origin, such as pyrethram,
tobacco, derris, and cube, it is necessary to extract the Active principles
by the use of an organic solvent. An improved lare-capcity apparptus in
which these extractions can be made was devised and described (Drake and
Spies, 192), as was also (Schechter And T{ller, 3c7) an automatic continu-
ous cp-rcolator useful for the same purpose.

The prticle size of insecticides has grent influence on their effi-
cacy, but hiratofore no simple pparntus was kown by which this could be
determined. A new differential manometer type sedimentation apparatus was
devised by Goodhue and C. M. Smith (315), by means of which the particle
size of many insecticidal dusts may be accurately determined. A simrler
apparatus for getting average particle size has recently been developed by
Gooden and Smith (awaitin publication).

In order to determiine arsenic, lead, copptr, mercury, and other
metals on fruits Pnr ver-Ptablos and in timbers treated with termite-proofine
materials or wood preservatives, it is necessary first to osidize completely
all the oranic material present. An improve! apparatus for accomplishing
this oxidation was developed and described (Barnes, 49). A convenient
portable rack for handling the glass flasks used in this operation was
also described (Rusk, 313).

CREMOTROPI SM

The study of repellents for driving insects away from man and domes-
tic Animals or growing crops, and of attrpctpnts for luring them to roisoned
bits or traps is embraced in the term chemotropism.

The w-.ork of the chemists of the Division of Insecticide Investiga-
tions in cooperation with 2ishopp (1, 20, 123) and associates in this fielV
has led to the use of pine-tar oil for repelling the screwworm fly and other
blowflies from the wounds of cattle, sheep, goats, and other animals. This
insect causes an estimated annual loss of nearly 5 million dollars in the
United States, a loss which woulO be much greater except for the use of this
remedy.

In audition to the development of a practical treatment for screw-
worms in livestock, these cooperative investigations brought to light infor-
mation of theoretical value, such ass the relation between the chemical con-
stitution and phvysical properties of organic comroun0s and their repellent
value against blowflies, the specificity of insecticides, the influence of
volatility and other physicAl properties on repellent Vrlue, etc. This






37 -

'information'has perve4 helpful in the development .of insecticides for the
control of other-insedt petts.

Certain amyl-esters of salicyrlic Pcid -.ve been found to be useful
as attractants for the tobacco hornwQrm moth by the Division of TPruck Crop
and Garden Insects Investigations. The preparation and physical properties
of these were studied and. describ prl (FrieenAn and Haller, 40).

P.HARMACOLOGIAL IN~v$TIGATIOV5S

The- importance of ascertaining whether new synthetics -nd nelw prin-
civles isolatedfrominsecticida p~l~nts Axe deleterious tozmkn. was re alized
at the start of our! work. Cooperative work was, done in, 1929 with Dr. D. T.
Buckingham, a prom-nentj veterinarian of Washington, D. C., in testing the
action of rotenone: upon dogs (Ind. Eng. Chem. 22:113-113.. 1930). Later
Dr. H. B. Haag, Profess.or of Pharmacolo.7 at the Medical College of Virginia,
at Richmond, Va., was engpged as a collaborator and riven the problem of
studying- the- pharmaco-]rogy of -derris.

A report by :Haag* (119.) on the toxicolo y of rotenone, one of the.
chief constituents of derris, cube, and tinbo, was made in 1931., Later the
pharmacoloical testing of insecticides was transferred to the Food Research
Division of the Bureau of Agricultural Chemistry Pnd Engineering,, nd fur-
ther reports on derris Pnd its constituents have issued from that bureau
(Ind. Eng. Chem. 29: g15-821. 1936; ibid. 29: 420-431. 1937; ibid. 30: 592-
595. 193g). All this work- was done Pt Richmond, Vq., under the direction
of Dr. Haag. Brieflyit n 7 e st.d te4thet, when taken by mouth, rotenone
is only one-thirtieth ss toxic as lead arsenate to rabbits, and there ap-
pears to be no danger of either acute or chronic poisoning from eating cab-
bage, etc., treateA' #ith- derris -r cube, Dr., Taa.,.while connected with
the Division of I nectidide Invrstipations, Polso reported on the toxicology
of anabailne (i9O), whichcloselv resormlles nicotine pharmacoloricplly as
well as pli4sicsilly, chenically, and insecticidally. At the request nf the
Division of Insecticide Investigations, pharmacological studies of pheno-
thiazine and other syAthotic insecticides hsve been carried out by the
Bureau of Agricultural Chemistr., and 7npineerine at San Francisco, Calif.,
but are not'repbttd on here.

MOTTPROOFING

Clothes moths cause dana-e in the United States estimated at not
less than $20,0O0,00% annually. Additional damage is caused by furniture
beetles tnd'carpet beetles attacking upholstpred furniture, ris, furs,
wool, mohair, feathers, nnd other products containing keratin. Some Puthori-
ties h.ve figuiued-the yearly danege causes by fabric pests plus the cost of
insecticides, cedar closets, garment brgs, etc.. at not less than $100,000,0 .

Accomplishments of the Division of Insicticico Inv.stipstions in co-
-operation With entomologists of the Bureau.in this. field include the dis-
covery ,that .totenorne is a mothproofing agent (Back, Cotton, and Roafk, S5).
Although txpbsure .-to dir-ect sunlight .and air decomposes rotenone into in-
secticida~lly iane-t -subistapces, it does retain its remarkably high toxicity
to clothes moth larvae under ordinary household conditions sufficiently
long to enable it to be used in a practical way. This use of rotenone was
also discovered by W. J. McGill (U. S. patent 1,g54,949g) and has been com-







mercially exploited by the Standard Oil Conpany of Indiana.

The literature of mothproofing, which is largely:in patents, has been
thoroughly abstracted, and these abstracts have been published by Roark from
tire to time (15, 44, 46, 107, 145). The threat indexes of patented moth-
proofing materials (106, 170, 277) put out by Roark and Busboy constitute
the most complete compilation of information on the subject and have been
widely usedby workers in this field.

TRE MEDICATION

The idea of introd'lcing chemicals into the sap stream of a living
plant in order to control diseases, insects, or fungi attacking the plant
is ah old one. Although this procedure has been somewhat discredited by
.the extravagant claims of quacks pretending to be tree doctors, beneficial
results from the injection of certain copounds into trees have been report-
ed. Preliminary to an investigation of this field of tree medication, the
literature has been reviewed and a list made of the principal chemicals that
have been proposed for this purpose (Carter, 433).

Several thousand analyses of sections of trees were made for the Di-
vision of Forest Insect Investigations to aia in tracing the flow of solu-
tions of copper sulfate, sodium fluoride, zinc chloride, mercuric chloride,
and other chemicals when injected into tree trunks for the control of bark
beetles. New methods of analyzing impregnated wood were developed (Carter,
Capen, and Cassil, 403).

ECONOMICS OF INSECTICIDES

This subject has received attention, Ps shown by the following publi-
cations by Roark:

Economic aspect's of the Ause of insecticide's, (7)
United States ihsecticide statistics for 142 (36)
The American market for tuba root (Dprris elliptica) (77)
Problems in the production -nd use of insecticides in the South (T)
Insecticides and fungicides (24)
Insecticides and fungicides, lqlg-1939 (394)

Although not complete, our compilstion of statistics (394) of the
consumption of insecticides and fungicides in the United States during 1q36
is the best that has been published and hRs been widely quoted.

Additional compilations of figures on the use of certain insecticides
have been prepared, as, for example, statistics nf rotenone-benring roots
that are Piven in publications 159, I4, 279, anA 4lq, also by Ronrk.

BIBLIOGRAPFI-S, ABSTRACTS, AND PREVI3WS

Information concerning insecticides is widely scattered, not only in
the entomolopical and agricultural literature but Also in the chemical,
patent, pharmaceutical, medical, and veterinary literature. No one nbstract
journal covers all this literature, PnO it is exceedingly difficult for the
student of insecticides t" keep abreast of developments in this field. In
order to assist in making information on insecticides available to those


- 39-





-39-

interested in chemical methods of pest control, the Division of Insecticide,
InvestigatLone has compiled and-published a number of biblioeraphies on
some' of the more important insecticides, such as manganese arsenate (Dear-
born,.33), magnesium arsente (Dearborn, 411), sprny residues of arsenic,
lead, fluorine, nicotine, etc., Pnd their removal (Busbey, 431), fluorine
compounds (Carter and Bnsbny, 432), chloropicrin (79, 209, 25 ), ethylene
dichloride (132), ethylene oxide (247)'; c:ranide compounmns (259, 29l, 299,
470, 476), chemicals used in treatments of trees by injections (433), nico-
tine (306, 319), derris (134, 414, .421, 434), Lonchocarpus (279, 419),
Tephrosia. (327), Quassia (449), and miscellaneous insecticidal plants (04,
112).

The demand for these publications has been widespread, necessitating
the reprinting of several.

ABSTRACTS OF PATENT LITERATURE

Beginning in 1926, abstracts of United States patents relptinz to
insecticides, fungicides, spraying, dustin-g and fumig-ating machinery, in-
sect traps, and other mpchn.nical devices for combatin.g- p-sts were prepared
by Roark and circulated. in mimeographed form. At present these abstracts
are issued monthly under the title "Review if Unite, States tentss Relat-
ing to Pest Control," and sent to 1,2i rers-)ns in this country rnd to 232
in foreign countries. Tis service is prertitvJ appreciated by eco-nomic ento-
molopists, insecticide manfactu(rs, rnd rest-contrnl operators. Many of
the abstracts are reprinted by 9-ap, the official journal of the National
Association of Insecticide and Disinfectant 1Tnufacturers, and by P-sts,
the official organ of the Natinal Pest Contril Association. The British
Pbstract journal Review of Applipri Int-moipy lso r-fe~rs to this patgnt
review.

From time to time the attention cef entonolerists has been called to
the value of the information cont.inePd in patents. The following papers on
this subject have been published by Roark:

Importance of patent literature to ec-nomic entomologists (3)
Insecticide patents (34)
The trend in pest-contr'l inventions in the United States (147)
A review of nonchemical United States patents issued from 1ql7 to
1933, inclusive, relating to insect control (254)

Comprehensive compilations of information taken from the patent
literature concerning certain classes of insecticides have beon issued. The
most complete of these relnte to moth.roofing (15, 44, 46, 106, 107, 145,
170, 277), to organic sulfur compounds used as insecticides and fungicides
(250), and to the rotenone-beerinp -ilqnts Derris, Lonchocprnus, and Tpnhro-
sia (76, 134, 211, 279, 327, 1o09. 41).

There were also issued by Rosrk 147 mimnocr-hd lists of United
States patents issued from 1917 to 1933, inclusive, relptinp to insect elec-
trocutors, trans, fly screens, flimic-atinp devices, dusting qnd strarying
apparatus, insect barriers, machinery for wnshinp insecticide sorav residues
from fruits And vettbles, etc. Thpse lists, which briefly abstracted
3,543 patents on these subjects, were distributed t- State entomologists
and plant pathologists end others interested in rest control, and constitute







the.,only comprehensive publication on nrnchepical meAns of pest control.
other than the original patents filed in the United States Patent Office.

An index of chemicals mentioned in the Review of United States Pat-
ents relating to Pest Control issued in 1931 was published by Roark (200).

BOOK REVIEWS

Because of their reputation as outstanding specialists in certain
fields of research, members of the Division of Insecticide Investigations
have been asked from time to time, by the editors of leading scientific
journals such as the Journal of the Association of Official Agricultural
Chemists, Industrial and 7,ngineerinp Chemistry, and Cereal Chemistry, to
prepare reviews of books on pyrethrum (Roark, 206), organic chemistry
(Haller, 280), theoretical chemistry (Nelson, 314), qualitative analysis
(Nplson, 360), fumigation (Roark, 3Th*, microchemical methods (Clark, 41l),
and insecticide statistics (Roark, 469).

POPULAR ARTICLES ON INSECTICIDES

Many popular articles presenting information on insecticides have
been published. The following titles indicate the scope of our activities
under this heading:

Modern methods of disinfecting and fumigatinp (5)
A report of the Insecticide Division's investigations with
various insecticides (9, 10)
Chemists in front ranks in warfare on harmful insects (12)
New insecticides developed to improve crop protection (50)
Some of the chrmicpl ?rhblems in codling m-th control (59)
Use of economic poisons to saforuar9 crors (114)
New fumigants for destrnyinp insect pests in foodstuffs (1l6)
Rotenone a promising new insecticide (133)
Chemically combatin- insect pests of foodstuffs (143)
Advantages and limitations of organic insecticides (239)
Recent developments in insecticide research (240)
Insecticides for combating household pests (271)
Research to find substitutes for lead arsenate (300)
An insect that breathes thrnuph its nose (345)
Agricultural products as insecticides (429)
Recent progress in the chemistry of pyrethrum flowers (443)

The difference between insecticides and fungicides was pointed out
in a brief note (392) and the term "derris r-sinate" criticized (4o4).

?APERS PR3PAR7,D BY INVITATION

By invitation of the National Research Council, a sprios of annual
reviews of the progress in insecticides and funr-icidr s in the United States
was prepared by Roark and-published in the Annual Survey of American Chem-
istry for 1929, 1930, 1931, 1933, and 1935 (57, 105, 14o, 218, 293). rpch
of these reviews summarizes the information from about 200 to 350 scientific
articles and patents. Also, by invitation, progress in thn chemistry of
heterocyclic comp ounds recorded by Anerican workers in 1031 (139) and 1932
(11) was reviewed and published by Haller and L. 7. Smith in the Annual
Surveys. By invitation frn the edito-s -f the Annual Review of Piochemistrv,
A chapter on develpnents during 1937 in organic insecticides of plant -ripin






-41 -
was prepared by LPFo-re nM Markwoo' for volume 7 of this work (393)

The literature -nd pntonts desc'in ,-rorress from June to November,
1939, in household insecticidles, espccirolly pyrethrum, derris, and synthet-
ics, was reviewed at the rpoupst of the National Association of Inspcticidp
and Disinfectant intnufacturprs (Roark, 42 ).

Other papers prepare4 by invitation include ITos. 5, 7, q, 10, 42,
50, 59, 78, 90, ll4, 477. Thpse arp discusperl under th subjects of which
they treat, such as pyrpthrum, derris, etc.




- 42 -


LIST OF PUBLICATIONS AND PATENTS

of the

DIVISION OF INSECTICIDE INVESTIGATIONS

R. C. Roark, Principal Chemist in Charge

for the period

July 1, 1927, to December 31, 1939


2ore of the publications listed below were prepared jointly by
me ,ers of the Division of Insecticide Investigations and those of other
organizations. The asterisk indicates the authors not connected with
this Division. Copies of these publications can doubtless be consulted
in almost any large public or institutional library.

PUBLICATIONS
Index
No.
1. Repellents for Blovflies. R. 7 Roark, D. C. Parman,* F. C,
Bishopp* and E. W. Laake.* Indus. and Engin. Chem., v. 19, no. 8,
p. 942-943, Aug. 1927,

2. Ethylene Dichloride-Carbon Tetrachloride Mixture; a New Non-Burn-
able, Non-Explosive Fumigant. R. T. Cotton* and R. C. Roark.
Jour. Econ. Ent., v. 20, no. 4, p. 636-639, Aug. 1927.

3. Importance of Patent Literature to Economic Entomologists. R, C.
Roark. Jour. Econ. Ent., v. 20, no. 4, p. 640-641, Aug. 1927.

4, An Apparatus for the Rapid Vaporization of Carbon Disulphide. C,
A. Weigel,* H. D. Young, and R. L. Swenson.* U. S. Dept. Agr.
Ciro. No. 7, 8 pp., Nov. 1927.

5. b1odern Methods of Disinfecting and Fumigating. R. C. Roark
National Safety News, v. 17, no. 1, p. 23-24, Jan. 1928.

C, Fuigation Tests with Certain Aliphatic Chlorides. R. C. Roark
a Rd T. Cotton.* Jour. Econ. Ent., v. 21, no. 1. p. 135-142,
Feb. 1928.

7 Econouic Aspects of the Use of Insecticides, R ". Roark. Chem,
Markets, v. 22, no. 3, p. 303-304, Mar. 1928.

8.Fungation of Stored-Product Insects with Certain Alkyl and Alky-
icne Formates. R. T, Cotton* and R. C. Roark. Indus. and Engin.
Chem., v. 20, no. 4, p. 380-382, Apr. 1928.
-- -- -- -he------------ -vision-- ------------
1Date of organization of the Division






- 43 -


9. Insecticide Investigations. R. C. Roark. U. S. Daily, 3(45): 9,
Apr. 25, 1928.

10. Tobacco and Gases as Insecticides. R. C. Roark. U. S. Daily,
3(46): 11, Apr. 26, 1928.

11. Insecticidal Action of Some Esters of Halogenated Fatty Acids in
the Vapor Phase, R. C. Roark and R. T. Cotton.* Indus. and
Engin. Chem., v. 20, no. 5, p. 512-514, May 1928.

12. Chemists in Front Ranks in Warfare on Harmful Insects. F C.
Roark. U. S. Dept, Agr, Yearbook-1927, p. 177-179. July 1928.

13. Dipiperidyls. C. R. Smith. Jour. Amer. Chem. Soc., v, 50, no. 7,
p. 1936-1938, July 1928.

14. Effect of Alkalinity on Basic Cupric Sulfates. 0. A. Nelson.
Jour. Phys. Chem., v. 32, no, 8, p. 1185-1190, Aug. 1928.

15. Chemically Combating Clothes Moths. R, C. Roark. Soap, v. 3,
no. 12, p. 95, 97, 99, 101, Aug. 1928.

16. Ethylene Oxide as a Fumigant. R. T. Cotton* and R. C. Roark.
Indus. and Engin. Chem., v. 20, no. 8, p. 805, Aug. 1928.

17. The Preparation of Alpha-, Beta- and Gamma-Benzylpynridines. F, B,
LaForge. Jour. Amer. Chem. Soc.. v. 50, no. 9, p. 2484-2487,
Sept. 1928.

18, The Preparation of Some Pyrrolidine Derivatives. F. B. LaForge.
Jour. Amer. Chem. Soo., v. 50, no. 9, p. 2471-2477, Sept. 1928.

19. The Preparation and Properties of Some New Derivatives of Pyri-
dine. F. B. LaForge. Jour. Amer. Chem. Soc., v. 50, no 9,
p. 2477-2483, Sept. 1928.

20. Tests of Blowfly Baits and Repellents During 1926. 0. C. Parnan,*
E. W. Laake,* F. C. Bishopp,* and R. C. Roark. U. S. Dept. Agr
Tech. Bull. no. 80, 14 pp., Sept. 1928.

21. Composition of Fluorides and Fluosilicates Sold as insecticides.
R. H. Carter and R. C. Roark. Jour. Econ. Ent., v. 21, no. 5,
p. 762-773, Oct. 1928.

22. Solubilities of Some Inorganic Fluorides in Water at 250 C. R. H.
Carter. Indus. and Engin. Chem., v. 20, no. 11, p. 1195, Nov.
1928.

23. Vapor Pressures of Fumigants. I. Methyl, Ethyl, Isopropyl, and
Secondary Butyl Chloroacetates. 0. A. Nelson. Indus. and Engin.
Chem., v. 20, no. 12, p. 1380-1382, Dec. 1928.





-44 -
Index
No.
24. Vapor Pressures of Fumigants. II. Methyl, Ethyl, n-Propyl,
Isopropyl, n-Butyl, Secondary Butyl. and Isobutyl Formates. 0. A.
Nelson. Indus. and Engin. Chem., v. 20, no. 12, p. 1382-1384,
Dec. 1928.

25. Some Recently Proposed Methods for the Assay of Pyrethrum Flowers.
R. C. Roark. Oil, Paint and Drug Reporter, v. 114, no. 27, p. 50,
Dec. 1928. Also published under Chemical Estimation of Pyrethrum.
Soap, v. 4, no. 7, p. 101, Mar. 1929.

26. Sampling Apples in the Orchard for the Determination of Arsenical
Spray Residue. J. W. Barnes. Indus. and Engin. Chem., v. 21,
no. 2, p. 172-174, Feb. 1929.

27. Vapor Pressures of Fumigants. IV. Vapor Pressure of Nicotine.
H. D. Young and 0. A. Nelson. Indus. and Engin. Chem., v. 21,
no. 4, p. 321-322, Apr. 1929.

28. Recent Progress in the Chemistry of Derris. R. C. Roark. Jour.
Econ. Ent., v. 22, no. 2, p. 378-381, Apr. 1929.

29. Maximum Weights of Various Fumigants which can Exist in Vapor
Form in a 1,000 Cubic Foot Fumigating Chamber. R. C. Roark and
0. A. Nelson. Jour. Econ. Ent., v. 22, no. 2, p. 381-387, Apr.
1929.

30. The Use of Carbon Dioxide to Increase the Insecticidal Efficacy
of Fumigants. R. T. Cotton* and H. D. Young. Proceedings of the
Entomological Society of Washington, v. 31, no. 5, p. 97-102,
May 1929.

31. Insect Poison Called Rotenone Highly Toxic but Costly at Present.
F. B. LaForge. U. S. Dept. Agr. Yearbook-1928, p. 388, June 1929.

32. Insecticide Residues Removed from Fruit by Various Washes. R. C.
Roark. U. S. Dept. Agr. Yearbook-1928, p. 389-390, June 1929.

33. Insecticide Research Develops a Promising Substitute for Nicotine.
C. R. Smith. U. S. Dept. Agr. Yearbook-1928, p. 388-389, June
1929.

34. Insecticide Patents. R. C. Roark. Jour. Econ. Ent., v. 22, no. 3,
p. 596, June 1929.

35. Rotenone. I. Reduction Products of Rotenone. F. B. LaForge and
L. E. Smith. Jour. Amer. Chem. Soc., v. 51, no. 8, 2574-2581,
Aug. 1929.

36. United States Insecticide Statistics for 1928. R. C. Roark. Jour.
Econ. Ent., v. 22, no. 4, p. 699-701, Aug. 1929.






45 -

Index
No.
37. Evolution of Hydrocyanic Acid from Calcium Cyanide H. D. Young,
Indus. and Engin. Chem., v. 21, no. 9, p. 861-863, Sept, 1929.

38. Compatibilities of Insecticides. I. Fluosilicates and Cryolite
with Arsenates. R. H. Carter. Jour. Econ. Ent., v. 22. no. 5,
p. 814-818, Oct. 1929.

39. N .- solvents for the Re.r.ova! of Arsenical Spray Residue R. H.
Robinson. Indus. and Engin. Chem., v. 21, no. 11, p. 1132-1135,
Nov. 1929.

40. Sampling Cleaned Apples for Determination of Arsenical Spray
Residue. J. W. Barnes and C. W. Murray. Indus. and Engin. Chem.,
v. 21, no. 11, p. 1146-1147, Nov. 1929.

41. The Occurrence of Rotenone in the Peruvian Fish Poison "Cube"
E. P. Clark. Science, v. 70, no. 1820, p. 478-479, Nov. 15, 1929.

42. Valiosas Plantas Insecticidas Sudamericanas. R. C. Roark. Boletin
de la Union Panamericana, v. 63, p. 1298-1299, Dec. 1929.

43, New Solvents for the Active Principles of Pyrethrum, W, A.
Cersdorff and W. M. Davidson.* Indus. and Engin. Chem., v. 21,
no. 12, p. 1251-1253, Dec. 1929.

44. Some Recently Proposed Stomach Insecticides. a Review of the Patent
Literature. R. C. Roark. Trans. Fourth Internatl. Cong. Ent.
Ithaca, Aug. 1928, v. 2, p. 728-736, Dec. 1929.

45. Effect of Various Fumigants on the Germination of Seeds. H. D
Young. Jour. Agr. Research, v. 39, no. 12, p. 925-927, Dec. 15,
1929.

46. Recent Mothproofing Patents. R. C. Roark. Textile Colorist,
v. 51, no. 612, p. 828-830, Dec. 1929; v. 52, no. 613, p. 25-28,
Jan. 1930.

47. 5kraup's Reaction Applied to the Phenylenediamines. Preparation
of the Phenanthrolines and Related Dipyridyls, C, R Smith
Jour. Amer. Chem. Soc., v. 52, no. 1, p. 397-403, Jan, 1930.

48. Accuracy of the Gutzeit Method for the Determination of Minute
Quantities of Arsenic. J. W. Barnes and C. W. Murray. Indus. and
Engin. Chem. Anal. Ed., v. 2, no. 1, p. 29-30, Jan. 15, 1930.

49. Apparatus for Destructive Oxidation of Organic Material in the
Determination of Metals in Foods. J. W. Barnes. Indus. and
Engin. Chem. Anal. Ed., v. 2, no. 1, p. 107-108, Jan. 15, 1930.





46 -
Index
No.
50. New Insecticides Developed to Improve Crop Protection. R. C.
Roark. U. S. Daily, v. 4, no. 274, p. 8, Jan. 23, 1930.

51. Rotenone. II. The Derivatives of Derritol. F. B. LaForge and
L. E. Smith. Jour. Amer. Chem. Soc., v. 52, no. 3, p. 1088-1091,
March, 1930.

52, Rotenone. III. Dehydrorotenone. F. B. LaForge and L. E. Smith.
Jour. Amer. Chem. Soc., v. 52, no. 3, p. 1091-1098. Mar. 1930.

53. Rotenone. IV. Constitution of Rotenone. F. B. LaForge. Jour.
Amer. Chem. Soc., v. 52, no. 3, p. 1102-1104, Mar. 1930.

54. Tests of Various Aliphatic Compounds as Fumigants. R. C. Roark
and R. T. Cotton.* U. S. Dept. Agr. Tech. Bull. 162, 52 pp.,
Mar. 1930.

55. Insectiicidal Properties of Fluorine Open Wide Field for Investiga-
tion. R. H. Carter. U. S. Dept. Agr. Yearbook-1930, p. 332-334,
Mar. 1930.

56. Some Constituents of Derris and "Cube" Roots other than Rotenone.
E. P. Clark. Science, v. 71, no. 1841, p. 396, Apr. 11, 1930.

57. Insecticides and Fungicides. R. C. Roark. Ann. Survey Amer.
Chem., v. 4, July 1, 1928 to December 31, 1929, p. 358-382, Apr.
1930.

58. Pyrethrum and Soap, a Chemically Incompatible Mixture. R. C.
Roark. Jour. Econ. Ent., v. 23, no. 2, p. 460-462, Apr. 1930.

59. Some of the Chemical Problems in Codling Moth Control. C. R.
Gross and J. E. Fahey. Northwest Fruit Grower, v. 2, nos. 32-33,
p. 7, 22, May-June 1930.

60. Toxicarol. A Constituent of the South American Fish Poison Cracca
(Tephrosia) toxicaria. E. P. Clark. Jour. Amer. Chem. Soc.,
v. 52, no. 6, p. 2461-2464, June 1930.

61. Rotenone. V. The Identity of Isotubaic and Rotenic Acids. H. L.
Haller and F. B. LaForge. Jour. Amer. Chem. Soc., v. 52, no. 6,
p. 2480-2483, June 1930.

62. The volubility of Rotenone. I. Solubility and Optical Rotation
in Certain Organic Solvents at 200 C. H. A. Jones and C. M. Smith.
Jour. Amer. Chem. Soc., v. 52, no. 6, p. 2554-2562, June 1930.

63. Physical and Chemical Properties of Commercial Arsenical Insecti-
cides. I, Manganese Arsenate. F. E. Dearborn. Jour. Econ. Ent.,
v. 23, no. 3, p. 630-635, June 1930.





-47 -

Index
No.
64. The Use of the Ethylene Oxide-Carbon Dioxide Mixture for Treating
Stored Grain. E. A. Back,* R. T. Cotton,* H. D. Young and J. H.
Cox.* Mimeographed, 10 pp., illus., July 1930.

65. Rotenone. VI. Derric Acid. F. B. LaForge and L E. Smith, Jour.
Amer. Chem. Soc., v. 52, no. 7, p. 2878-2881, July 1930.

66. Relative Insecticidal Value of Commercial Grades of Pyrethrum
C. C. McDonnell,* W. S. Abbott.* W. M. Davidson,* G. L. Keenan*
and 0. A. Nelson. U. S. Dept. Agr. Tech. Bull. 198, 9 pp., July
1930.

67. Solubilities of Fluosilicates in Water, R. H. Carter. Indus.
and Engin. Chem., v. 22, no. 8, p. 886-887, Aug. 1930.

68. Fluoaluminates of the Alkali Metals. R. H. Carter. Indus. and
Engin. Chem., v. 22, no. 8, p. 888-889, Aug. 1930.

69. Rotenone. VII. The Structure of Tubanol and Tubaic Acid. H. L.
Haller and F. B. LaForge. Jour. Amer. Chem. Soc., v. 52, no. 8,
p. 3207-3212, Aug. 1930.

70. A Method for the Study of Toxicity Using Goldfish. W. A. Gers-
dorff. Jour. Amer. Chem. Soo., v. 52, no. 8, p. 3440-3445,
Aug. 1930.

71. Physical and Chemical Properties of Commercial Arsenical Insecti-
cides. II. Magnesium Arsenate. F. E. Dearborn. Jour. Econ,
Ent. v. 23, no. 4, p. 758-764, Aug. 1930.

72. Additional Solvents for Increasing the Effici nG of Hydrochloric
Acid as a Cleaning Solution for Apples. 1. C. Diehl,* A. L.
Ryall* and Jack E. Fahey. Northwest Fruit Grower, v. 2, no. 35,
p.8 and 18, Aug. 1930; also mimeographed, 3 pp., 4 charts, Oct.
1930.

73. Vapor Pressures of Fumigants. IV. 1,1,2,2-Tetra-, Penta-. and
Hexachloroethanes. 0. A. Nelson. Indus. and Engin. Chem., v. 22,
no. 9, p. 971-972, Sept. 1930.

74. Rotenone. VIII. Isomeric Hydroxy Acids and Their Relation to
Dehydrorotenone. F. B. LaForge and L. E. Smith. Jour. Amer.
Chem. Soc., v. 52, no. 9, p. 3603-3609, Sept. 1930.

75. Mannitol from apophyton cimicidum. N. L. Drake and Joseph R.
Spies. Jour. Amer. Chem. Soc., v. 52, no. 9, p. 3739, Sept. 1930

76. Derris, Cube and Tephrosia as Insecticides. A Review of American
and Foreign Patents. R. C. Roark. Soap, v. 6, no. 1, p. 105,
107, 109, Sept. 1930.





- 48 -


Index
No.
77. The American Market for Tuba Root (Derris elliptica). R. C.
Roark. The Malayan Agri. Jour., v. 18, no. 9, p. 455-458, Sept.
1930.

78. Problems in the Production and Use of Insecticides in the South.
R. C. Roark. Jour. Chemical Education, v. 7, no. 10, p. 2301-
2306, Oct. 1930.

79. Supplement to Chloropicrin Bibliography. W. A. Gersdorff. Mimeo-
graphed, 19 pp., Oct. 1930.

80. Neonicotine and Certain Other Derivatives of the Dipyridyls as
Insecticides. C. R. Smith, C. H. Richardson* and H. H. Shepard.*
Jour. Econ. Ent., v. 23, no. 5, p. 863-867, Oct. 1930.

81. Suggestions for the Use of Additional Solvents for Increasing
Effici.ency of Hydrochloric Acid as a Cleansing Solution for
Apples. H. C. Diehl* and Jack E. Fahey. Mimeographed, 2 pp.,
Oct. 1930.

82. Rotenone. IX. Alkali Fusion of Some Derivatives of Rotenone.
H. L. Haller and F. B. LaForge. Jour. Amer. Chem. Soc., v. 52,
no. 11, p. 4505-4509, Nov. 1930.

83. Rotenone. X. Cleavage of Derritol and Rotenol. L. E. Smith and
F. B. LaForge. Jour. Amer. Chem. Soc., v. 52, no. 11, p. 4595-
4598, Nov. 1930.

34. Densities of Mixtures of Air and Various Fumigants. R. C. Roark
and 0. A. Nelson. Jour. Econ. Ent., v. 23, no. 6, p.985-987,
Dec. 1930.

85. Rotenone as a Mothproofing Agent. E. A. Back,* R. T. Cotton*
and R. C. Roark. Jour. Econ. Ent., v. 23, no. 6, p. 1014, Dec.
1930.

86. The Toxicity of Rotenone. Isorotenone and Dihydrorotenone to
Goldfish. W. A. Gersdorff. Jour. Amer. Chem. Soc., v. 52, no.
12, p. 5051-5056, Dec. 1930.

87. A Relation between Rotenone, Deguelin and Tephrosin. E. P. Clark.
Science, v. 72, no, 1879, p. 17-18, Jan. 2, 1931.

88. Neonicotine and Isomeric Pyridylpiperidines. C. R. Smith. Jour.
Amer. Chem. Soc., v. 53, no. 1, p. 277-283, Jan. 1931.

89. Deguelin. I. The Preparation, Purification and Properties of
Deguelin. a Constituent of Certain Tropical Fish-Poisoning Plants.
E. P. Clark. Jour. Amer. Chem. Soc., v. 55, no. 1, p. 313-317.
Jan. 1931.






49 -

Index
No.
90. The Use of Rosin in Insecticides and Disinfectants. R. C. Roark.
Proc. American Society for Testing Materials, Philadelphia, Pa.,
v. 30, part 2, 1930; Symposium on Rosin, held June 23-27, 1930,
p. 43-44, Jan. 1931.

91. The Composition of Commercial Calcium Arsenate. C. 14. Smith and
C. W. Murray. Indus. and Engin. Chem., v. 23, no. 2, p. 207-208,
Feb. 1931.

92. Tephrosin. I. The Composition of Tephrosin and Its Relation to
Deguelin. E. P. Clark. Jour. Amer. Chem. Soc., v. 53, no. 2,
p. 729-732, Feb. 1931.

93. Rotenone. XI. The Relation between Isorotenone and Rotenone.
H. L. Haller. Jour. Amer. Chem. Soc., v. 53, no. 2, p. 733-737,
Feb. 1931.

94. Plants Reputed to have Insecticidal Value; Plants Found in India.
R. C. Roark and G. L. Keenan.* Multigraphed, 22 pp., Feb. 1931.

95. Preparations Containing Rotenone for Use as Insecticides. I.
Aqueous Suspension. H. A. Jones and W. M. Davidson.* Jour. Econ.
Ent. v. 24, no. 1, p. 244-257, Feb. 1931.

96. Change in Toxicity of Rotenone in Solution and Suspension. W. M.
Davidson* and H. A. Jones. Jour. Econ. Ent., v. 24, no. 1, p. 257-
262, Feb. 1931.

97. The Incompatibility of Lime with Fluosilicates. R. H. Carter.
Jour. Econ. Ent., v. 24, no. 1, p. 263-268, Feb. 1931.

98. Genuine Derris Root May Contain no Rotenone. R. C. Roark. Jour.
Econ. Ent., v. 24, no. 1, p. -328, 330, Feb. 1931.

99. The Insecticide Possibilities of Derris Root. R. C. Roark. Soap,
v. 7, no. 3, p. 97, 99, 101, Mar, 1931.

100. Fluorine Compounds as Substitutes for Lead Arsenate in the Control
of the Codling Moth, E. J. Newcomer* and R. H. Carter. Proc. 26th
Annual Meeting of Washington State Hort. Assn. Dec. 8-10, 1930,
p.73-76. Mar. 1931; Also published in Proc. 36th Annual Meeting
Idaho State Hort. Assn., Feb. 10-12, 1931, pp. 161-165.

101. Decomposition of Rotenone in Solution. H. A. Jones. Indus. and
Engin. Chem., v. 23, no. 4, p. 387-388, Apr. 1931.

102. Determination of Barium Fluosilicate Spray Residue. R. H. Carter.
Indus. and Engin. Chem. Anal. Ed., v. 3, no. 2, p. 146-147, Apr.
15, 1931.






- 50 -


Index
No.
103. A Study of the Toxicity of Toxicarol, Deguelin and Tephrosin
Using the Goldfish as the Test Animal. W. A. Gersdorff. Jour.
Amer. Chem. Soc., v. 53, no. 5, p. 1897-1901, May 1931.

104. 2,4,5-Trimethoxybenzoic Acid: A Derivative of Dehydrodeguelin.
E. P. Clark. Jour. Amer. Chem. Soc., v. 53, no. 5, p. 2007-2008,
May 1931.

105. Insecticides and Fungicides. R. C. Roark. Ann. Survey of American
Chemistry, v. 5, 1930, p. 398-421, May 1931.

106. An Index of Patented Mothproofing Materials. R. C. Roark. Mimeo-
graphed, 125 pp., May 1931.

107. Recent Progress in Mothproofing. R. C. Roark. Textile Colorist,
v. 53, no. 629, p. 301-305, May 1931.

108. Toxicarol. II. Some Acetyl Derivatives of Toxicarol. E. P. Clark.
Jour. Amer. Chem. Soc., v. 53, no. 6, p. 2264-2271, June 1931.

109. Rotenone. XII. Some New Derivatives of Rotenol. H. L. Haller and
F. B. LaForge. Jour. Amer. Chem. Soc., v. 53, no. 6, p. 2271-2275,
June 1931.

110. The "Yellow Compounds" Resulting from the Decomposition of Rotenone
in Solution. H. A. Jones and H. L. Haller. Jour. Amer. Chem.
Soc., v. 53, no. 6, p. 2320-2324, June 1931.

Ill. Deguelin. II. Relationships between Deguelin and Rotenone. E. P.
Clark. Jour. Amer. Chem. Soc., v. 53, no. 6, p. 2369-2373, June
1931.

112. Excerpts from Consular Correspondence Relating to Insecticidal and
Fish Poison Plants. R. C. Roark. Mimeographed, 39 pp., June 1931.

113. Crystalline Solvates of Rotenone. H. A. Jones. Jour. Amer. Chem.
Soc., v. 53, no. 7, p. 2738-2741, July 1931.

114. Use of "Economic Poisons" to Safeguard Crops. R. C. Roark. U. S.
Daily, v. 6, no. 117, p. 8, July 20, 1931.

115. Rotenone. XIII. Oxidation of Methylderritolic Acid and the
Synthesis of 2,3,5- and 2,3,6-Trimethoxybenzoic Acids and Their
Derivatives. L. E. Smith and F. B. LaForge. Jour. Amer. Chem.
Soc., v. 53, no. 8, p. 3072-3077, Aug. 1931.

116. New Fumigants for Destroying Insect Pests in Foodstuffs. R. C.
Roark. Food Industries, v. 3, no. 9, p. 398-399, Sept. 1931.







51 -

Index
No.
117. Rotenone. XIV. The Relation of the Optical Activity of Some
Rotenone Derivatives to the Structure of Tubaic Acid. H. L.
Hailer and F. B. LaForge. Jour. Amer. Chem. Soc., v. 53, no. 9,
p. 3426-3431, Sept. 1931.

118. Deguelin. III. The Orientation of the Methoxyl Groups in Deguelin
Tephrosin and Rotenone. E. P. Clark. Jour. Amer. Chem. Soc.,
v. 53, no. 9, p, 3431-3436, Sept., 1931.

119. Toxicological Studies of Derris elliptica and Its Constituents i.
Rotenone. H. B. Haag. Jour. Pharm. and Exper. Therapeutics,
43, no. 1, p. 193-208, Sept. 1931.

120. Rotenone. XV. The Structure of Derric Acid. F. B. LaForge. Jour.
Amer. Chem. Soc., v. 53, no. 10, p. 3896-3901, Oct. 1931,

121. Neonicotine Recently Found as an Alkaloid in Anabasis apylia L.
C. R. Smith. Jour. Econ. Ent., v. 24, no. 5, p. 1108, Oct. 19311

122. Carbon Tetrachloride May Replace Ether in the Extraction of
Rotenone. Preliminary Report. H. A. Jones. Indus. and Fngin.
Chem. News Edition, v. 9, no. 19, p. 301, Oct. 10, 1931.

123. The Chemotropic Responses of the House Fly, the Greon-Bottle
Flies, and the Black Blowfly. E. W. Laake,* D. C, Parman,-
F. C. Bishopp* and R. C. Roark. U. S. Dept. Agri. Tech. Bull.
270, 10 pp., Nov. 1931.

124. Rotenone. XVI. Interpretation of Some Characteristic Reactions of
Rotenone. F. B. LaForge, H. L. Haller and L. E. Smith. Jour
Amer. Chem. Soc., v. 53, no. 12, p. 4400-4408, Dec, 1931.

125. Rotenone. XVII. Note on the Dimorphic Forms of Dihydrorotenone.
F. B. LaForge and G. L. Keenan.* Jour. Amer. Chem. Soc., v. 53,
no. 12, p. 4450-4451, Dec. 1931.

126. Rotenone. XVIII. Cleavage of the Oxide Ring in Tubaic Acid.
H. L. Haller and F. B. LaForge. Jour. Amer. Chem. Soc., v. 53,
no. 12, p. 4460-4462, Dec. 1931.

127. Identity of Neonicotine and the Alkaloid Anabasine. C. R. Smith.
Jour. Amer. Chem. Soc., v. 54, no. 1, p. 397-399, Jan. 1932.

128. Binary System Carbon Tetrachloride-Ethylene Dichloride Their
Boiling Points and Specific Gravities as Aids in Analysis. H. D.
Young and 0. A. Nelson. Indus. and Engin. Chem. Anal. Ed., v. 4,
no. 1, p, 67-69, Jan. 1932.






- 52 -


Index
No.
129. Rotenone. XIX. The Nature of the Alkali Soluble Hydrogenation
Products of Rotenone and Its Derivatives and Their Bearing on the
Structure of Rotenone. F. B. LaForge and H. L. Haller. Jour.
Amer. Chem. Soc., v. 54, no. 2, p. 810-818, Feb. 1932.

130. The Toxicity of Certain Plant Extracts to Goldfish, N. L. Drake
and J. R. Spies. Jour. Econ. Ent., v. 25, no. 1, p. 129-133,
Feb. 1932.

131. The Viebock and Schwappach Method for the Determination of Methoxyl
and Ethoxyl Groups. E. P. Clark. Jour. Assoc. Off. Agr. Chem.,
v. 15, no. 1, p. 136-140, Feb. 1932.

132, Bibliography of Ethylene Dichloride. W. A. Gersdorff. U. S.
Dept. Agr. Misc. Publication No. 117, 60 pp., Feb. 1932.

133. Rotenone, A Promising New Insecticide. H. A. Jones. The Hexagon
of Alpha Chi Sigma, v. 22, no. 6, p. 276-280, Mar. 1932.

134. A Digest of the Literature of Derris (Deguelia) Species Used as
Insecticides, 1747-1931. R. C. Roark. U. S. Dept. Agri. Misc.
Publication No. 120, 86 pp., Apr. 1932.

135. An Apparatus for Measuring Partial Vapor Pressures of Binary
Liquid Systems. 0. A. Nelson. Jour. Amer. Chem. Soc., v. 54,
no. 4, p. 1390-1393, Apr. 1932.

136. Toxicarol. III. A Relation Between Toxicarol and the Rotenone
Group of Fish Poisons. E. P. Clark. Jour. Amer. Chem. Soc.,
v. 54, no. 4, p. 1600-1602, Apr. 1932.

137. Rotenone. XX. The Structure of Tubaic Acid. H. L. Haller and
F. B. LaForge. Jour. Amer. Chem. Soc., v. 54, no. 5, p. 1988-
1994, May 1932.

138. Rotenone. XXI. The Structure of Isorotenone, beta-Dihydrorotenone
and Dehydrorotenol. H. L. Haller. Jour. Amer. Chem. Soc., v. 54,
no. 5, p. 2126-2128, May 1932.

139. Heterocyclic Compounds. H. L. Haller and L. E. Smith. Ann,
Survey of American Chemistry, v. 6, 1931, p. 254-281, May 1932.

140. Insecticides and Fungicides. R. C. Roark. Ann. Survey of American
Chemistry, v. 6, 1931, p. 380-407, May 1932.

141. Compatibility of Acid Lead Arsenate with Commercial Oil Emulsions
as Used in the Pacific Northwest. C. W. Murray. Proc. 27th Annual
Meeting of the Washington State Horticultural Association, held
Dec. ist, 2nd and 3rd, 1931 at Yakima, Wash., p. 52-56, May 1932.







53-

Index
No.
142. The Effect of Fish and Mineral Oil Sprays in Problems of Arsenical
Spray Residue Removal. H. C. Diehl* and Jack E. Fahey. Proc,
27th Annual Meeting of the Washington State Horticultural Associa-
tion, held Dec. 1st, 2nd and 3rd, 1931 at Yakima, Wash., p.
57-60, May 1932.

143. Chemically Combatting Insect Pests of Foodstuffs. R. C. Roark.
Indus. and Engin. Chem., v. 24, no. 6, p. 646-648, June 1932.

144. Toxicarol. IV. Concerning the Structure of Toxicarol. E. P.
Clark. Jour. Amer. Chem. Soc., v. 54, no. 6, p. 2537-2548,
June 1932.

145. A Review of Recent Mothproofing Patents. R. C. Roark. Textile
Colorist, v. 54, no. 642, p. 369-374, June 1932.

146. Calcium Fluosilicate Compound is not Calcium Fluosilicate. R. H.
Carter. Jour. Econ. Ent., v. 25, no. 3, p. 707-709, June 1932.

147. The Trend in Pest Control Inventions in the United States. R. C.
Roark. Jour. Econ. Ent., v. 25, no. 3, p. 730-731, June 1932.

148. The Toxicity to Goldfish of Certain Organic Thiocyanates and
Isothiocyanates. N. L. Drake and R. L. Busbey. Jour. Amer.
Chem. Soc., v. 54, no. 7, p. 2930-2935, July 1932.

149. Two Constituents of Parosela barbata (Oerst.) Rydb. J. R. Spies
and N. L. Drake. Jour. Amer. Chem. Soc., v. 54, no. 7, p. 2935-
2938, July 1932.

150, Rotenone. XXII. Some New Data in Confirmation of the Structure of
Rotenone. L. E. Smith and F. B. LaForge. Jour. Amer. Chem. Soc.,
v. 54, no. 7, p. 2996-3000, July 1932.

151. Deguelin. IV. The Structure of Deguelin and Tephrosin. E. P.
Clark. Jour. Amer. Chem. Soc., v. 54, no. 7, p. 3000-3008, July
1932.

152. Rotenone. XXIII. The Structure of Rotenone. F. B. LaForge.
Jour. Amer. Chem. Soc., v. 54, no. 8, p. 3377-3380, Aug. 1932.

153. The Effect of Fish Oil Sprays on Spray Residue Removal. A Lloyd
Ryall* and Jack E. Fahey. Northwest Fruit Grower, v. 4, no. 8,
p. 4, Aug. 1932.

154. Composition of Certain Spreaders Used with Acid Lead Arsenate and
Compatibility of the Same. C. W. Murray. Northwest Fruit Grower,
v. 4, no. 9, p. 4, Sept. 1932.






- 54 -


Index
No.
155. Tephrosin. II. Isotephrosin. E. P. Clark and H. V. Claborn.
Jour. Amer. Chem. Soc., v. 54, no. 11, p. 4454-4456, Nov. 1932,

156. The Chemical Composition of Commercially Available Fluorine Com-
pounds. R. H. Carter. Jour. Econ. Ent., v. 25, no. 6, p. 1224-
1227, Dec. 1932.

157. The Incompatibility of Barium Fluosilicate and Nicotine Sulfate.
R. H. Carter. Jour. Econ. Ent., v. 25, no. 6, p. 1242-1243,
Dec. 1932.

158. Fluorine Residues on Apples. R. H. Carter. Jour. Econ. Ent.,
v. 25, no. 6, p. 1243-1244, Dec. 1932.

159. Derris Now Produced and Used on a Large Scale. R. C. Roark.
Jour. Econ. Ent., v. 25, no. 6, p. 1244-1245, Dec. 1932.

160. Rotenone. XXIV. Synthesis of Tetrahydrotubano!. H. L. Haller.
Jour. Amer. Chem. Soc., v. 54, no. 12, p. 4755, Dec. 1932.

161. A Method for Determining the Quantity of Mineral Oil Retained by
Leaf Surfaces after Spraying. L. H. Dawsey and A. J. Haas.*
Jour. Agr. Research, v. 46, no. 1, p. 41-49, Jan. 1, 1933.

162. Improved Method of Sealing the Capillary Tubes in the Rast Modifi-
cation of the Barger Method of Molecular Weight Determination.
J. R. Spies. Jour. Amer. Chem. Soc., v. 55, no. 1, p. 250, Jan.
1933.

163. Note on the Occurrence of Dehydrodeguelin and Dehydrotoxicarol in
Some Samples of Derris Root. E. P. Clark and G. L. Keenan.*
Jour. Amer. Chem. Soc., v. 55, no. 1, p. 422-423, Jan. 1933.

164. The Rotenone Content of Derris Root, Cube Root, and Other Plant
Materials. H. A. Jones. Jour. Wash. Acad. Sci., v. 23, no. 1,
p. 36-46, Jan. 15, 1933.

165. Assay of Plant Material for Its Rotenone Content. H. A. Jones.
Indus. and Engin. Chem. Anal. Ed., v. 5, no. 1, p. 23-26, Jan.
15, 1933.

166. Equipment for Laboratory Fumigations with Hydrocyanic Acid, with
Controlled Temperature and Humidity. H. L. Cupples. Indus. and
Engin. Chem. Anal. Ed., v. 5, no. 1, p. 36-38, Jan. 15, 1933.

167. Determination of Hydrocyanic Acid in Air and in Air-Carbon Dioxide
Mixtures. H. L. Cupples. Indus. and Engin. Chem. Anal. Ed., v. 5,
no. 1, p. 50-52, Jan. 15, 1933.










Index
No.
168. Interference of Pyridine Derivatives in Arsenic Determination.
C. R. Gross. Indus. and Engin. Chem. Anal. Ed., v. 5, no. 1,
p. 58-60, Jan. 15, 1933.

169. A Color Test for Rotenone. H. A. Jones and C. M. Smith. Indus.
and Engin. Chem. Anal. Ed., v. 5, no. 1, p. 75-76, Jan. 15, 1933.

170. A Second Index of Patented Mothproofing Materials. R. C. Roark.
Mimeographed, 109 pp., Feb. 1933.

171. Tephrosin. III. Some Acidic Derivatives of Tephrosin. E. P.
Clark. Jour. Amer. Chem. Soc., v. 55, no. 2, p. 759-762, Feb.
1933.

172. A Consideration of "Interval Shooting" as Practiced in Citrus
Fumigation. H. L. Cupples. Jour. Econ. Ent., v. 26, no. 1,
p. 262-269, Feb. 1933.

173. The Toxicity of Certain Plant Extracts to Goldfish. II. J. R.
Spies. Jour. Econ. Ent., v. 26, no. 1, p. 285-288, Feb. 1933.

174. A Study of the Toxicity of Rotenone Hydrochloride, Acetylrotenone
and Rotenolone Using the Goldfish as the Test Animal. W. A.
Gersdorff. Jour. Amer. Chem. Soc., v. 55, no. 3, p. 1147-1152,
Mar. 1933.

175. The Occurrence of Rotenone and Related Compounds in the Roots of
Cracca virginiana. E. P. Clark. Science, v. 77, no. 1995, p. 311-
312, Mar. 24, 1933.

176. Rotenone in a Species of Spatholobus. Howard A. Jones. Jour.
Amer. Chem. Soc., v. 55, no. 4, p. 1737-1738, Apr. 1933.

177. Loss in Toxicity of Deposits of Rotenone and Related Materials
Exposed to Light. Howard A. Jones, W. A. Gersdorff, E. L. Gooden,
F. L. Campbell* and W. N. Sullivan.* Jour. Econ. Ent., v. 26,
no. 2, p. 451-470, Apr. 1933.

178. The Relative Toxicity of Nicotine, Anabasine, Methyl Anabasine,
and Lupinine for Culicine Mosquito Larvae. F. L. Campbell,*
W. N. Sullivan,* and C. R. Smith. Jour. Econ. Ent., v. 26, no. 2,
p. 500-509, Apr. 1933.

179. The Determination of the Structure of Rotenone. F. B. LaForge,
H. L. Haller and L. E. Smith. Chem. Rev., v. 12, no. 2, p. 181-
213, Apr. 1933.






- 56 -


Index
No.
180, A Contribution to the Pharmacology of Anabasine. H. B. Haag.
Jour. Pharmacol. and Expt. Ther., v. 48, no. 1, p. 95-104, May 1933.

181. Heterocyclic Chemistry. H. L. Hailer and L. E. Smith. Ann.Survey
of American Chemistry, v. 7, 1932, p. 116-133, May 1933.

182. Microanalytical Methods. E. P. Clark. Jour. Assoc. Off. Agr.
Chem., v. 16, no. 2, p. 255-260, May 1933. 183.

183. Special Problems in the Removal of Spray Residues from Apples.
J. E. Fahey. Proc. of the 28th Annual Meeting of the Washington
State Horticultural Association, held Nov. 30, Dec. 1 and 2, 1932
at Wenatchee, Wash., p. 119-123, May 1933.

184. Rotenone. R. C. Roark. Indus. and Engin. Chem., v. 25, no. 6,
p. 639-642, June 1933.

185. Vapor Pressures of Fumigants. V. Alpha, Beta-Propylene Dichloride.
0. A. Nelson and H. D. Young. Jour. Amer. Chem. Soc., v. 55,
no. 6, p. 2429-2431, June 1933.

186. Arsenical Residues Found on Apples in the Pacific Northwest Through-
out a Season of Typical Spraying with Lead Arsenate. R. H. Carter
and E. J. Newcomer.* Jour. Econ. Ent., v. 26, no. 3, p. 572-580,
June 1933.

187. The Chemical Relationship between Certain Insecticidal Species of
Fabaceous Plants. R. C. Roark. Jour. Econ. Ent., v. 26, no. 3,
p. 587-594, June 1933.

188. A Laboratory Method for Determining Approximately the Evaporation
of Petroleum Spray Oils Under Field Conditions. L. H. Dawsey.
Jour. Econ. Ent., v. 26, no. 3, p. 735-736, June 1933.

189. A Comparison of the Toxicity of Nicotine and Anabasine. W. A.
Gersdorff. Jour. Amer. Chem. Soc., v. 55, no. 7, p. 2941-2945,
July 1933.

190. Rotenone. XXV. The Synthesis of Tetrahydrotubanol and Tetrahydro-
t-ubaic Acid. H. L. Haller, Jour. Amer. Chem. Soc., v. 55, no. 7,
p. 3032-3035, July 1933.

191. Rotenone. XXVI. Synthesis of the Parent Substances of Some Char-
acteristic Rotenone Derivatives. F. B. LaForge. Jour. Amer.
Chem. Soc., v. 55, no. 7, p. 1040-3048, July 1933.

192. A Simple Large-Capacity Extractor. Nathan L. Drake and Joseph R.
Spies. Indus. and Engin. Chem. Anal. Ed., v. 5, no. 4, p. 284,
July 15, 1933.





-57 -

Index
No.
193. Rotenone. XXVII. Note on the Hydrogenation of Rotenone. H. L.
Haller and P. S. Schaffer. Jour. Amer. Chem. Soc., v. 55, no. 8,
p. 3494-3495, Aug. 1933.

194. Casein Ammonia, A Practical Emulsifying Agent for the Preparation
of Oil Emulsions by Orchardists. E. J. Newcomer* and R. H. Carter.
Jour. Econ. Ent., v. 26, no. 4, p. 880-887, Aug. 1933.

195, The Relative Toxicity of Some Fluorine Compounds as Stomach Insec-
ticides. H. H. Shepard* and R. H. Carter. Jour. Econ. Ent., v. 26,
no. 4, p. 913, Aug. 1933.

196. Sources of Error in the Gutzeit Method for the Determination of
Arsenic. C. R. Gross. Jour. Assoc. Off. Agr. Chem., v. 16, no. 3,
p. 398-403, Aug. 15, 1933.

197. Semimicro Determination of Carbon and hydrogen. E. P. Clark. Jour.
Assoc. Off. Agr. Chem., v. 16, no. 3, p. 413-418, Aug. 15, 1933.

198. An Electrically Heated Sand Bath, E. P. Clark. Jour. Assoc. Off,
Agr. Chem., v. 16, no. 3, p. 418-420, Aug. 15, 1933.

199. Rotenone. XXVIII. Preparation of Dihydrorotenone. H. L. Haller
and P. S. Schaffer. Indus. and Engin. Chem., v. 25, no. 9, p. 983,
Sept. 1933.

200. An Index of Chemicals Mentioned in the Review of United States
Patents Relating to Pest Control Issued in 1931. R. C. Roark.
Mimeographed, 33 pp., Oct. 1933.

201. Studies of Fluorine Compounds for Controlling the Codling Moth.
E. J. Newcomer* and R. H. Carter. U. S. Dept. Agr. Tech. Bull. No.
373, 22 pp., Oct. 1933.

202. Notes on the Occurrence of Rotenone in Species of Derris and Lon-
chocarpus. Howard A. Jones. Jour. Wash. Acad. Sci., v. 23, no. 11,
p. 493-496, Nov. 15, 1933.

203. Semimicro Determination of Nitrogen by the Dumas Method. E. P.
Clark. Jour. Assoc. Off. Agr. Chem., v.16, no.4, p.575-580, Nov.1933.

204. Replacement of the Diazo Group by the Acetoxy Group. H. L. Haller
and P. S. Schaffer. Jour. Amer. Chem. Soc., v. 55, no. 12, p.
4954-4955, Dec. 1933.

205. Arsenic in Tobacco Smoke. C. R. Gross and 0. A. Nelson. Amer.
Jour. Pub. Health, v. 24, no. 1, p. 36-42, Jan. 1934.

206. Book Review of "Pyrethrum Flowers." by C. B. Gnadinger. R. C.
Roark. Indus. and Engin. Chem. News Edition, v. 12, no. 2. p. 33.
Jan. 20, 1934.





- 58 -


Index
No.
207. The Action of Acetic Acid on 3,4-Dimethoxylphenyldiazonium Boro-
fluoride. L. E. Smith and H. L. Haller. Jour. Amer. Chem. Soc.,
v. 56, no. 1, p. 237-239, Jan. 1934.

208. Methods for Determination of Lead in Foods. H. J. Wichmann,* C. W.
Murray, M. Harris,* P. A. Clifford,* J. H. Loughrey* and F. A.
Vorhes, Jr.* Jour. Assoc. Off. Agr. Chem., v. 17, no. 1, p. 108-
135, Feb. 1934.

209. A Bibliography of uhloropicrin, 1848-1932. R. C. Roark. U. S.
Dept. Agr. Misc. Publication No. 176, 88 p., Feb. 1934.

210. Derris in Fly Sprays. I. Kerosene Extracts of Derris Root as House
Fly Sprays Method and Results of Laboratory Tests of Extracts of
Derris and of Cube Roots. F. L. Campbell,* W. N. Sullivan..* and
Howard A. Jones. Soap, v. 10, no. 3, p. 81-83, 85, 87, 103, 107,
Mar. 1934.

211. A Review of Derris Patents Issued in Various Countries Recently
Covering Derris, Cube, and Tephrosia Insecticides. R. C. Roark.
Soap, v. 10, no. 3, p. 91, 95, 97, 99, Mar. 1934.

212. The Removal of Lead, Arsenic and Fluorine Residues from Apples.
Edwin Smith,* A. Lloyd Ryall,* C. R. Gross, R. H. Carter, C. W.
Murray and J. E. Fahey. Proc. 29th Annual Meeting of the Washington
State Horticultural Association, held December 4, 5, and 6, 1933 at
Yakima, Wash., p. 86-96, Mar. 1934.

213. A Further Study of the Toxicity of Derivatives of Rotenone with the
Goldfish as the Test Animal. W. A. Gersdorff. Jour. Amer. Chem.
Soc., v. 56, no. 4, p. 979-980, Apr. 1934.

214. Toxicarol. V. 7-Hydroxytoxicarol and Related Compounds. E. P.
Clark, Jour. Amer. Chem. Soc., v. 56, no, 4, p. 987-991, Apr. 1934.

215. Derris in Fly Sprays. II. Kerosene Extracts of Derris Root as
House Fly Sprays Comparative Tests of Extracts of Derris and of
Pyrethrum. F. L. Campbell,* W. N. Sullivan* and Howard A. Jones.
Soap, v. 10, no. 4, p. 83, 85, 103, 105, Apr. 1934.

216. Sulphur Fumigation of Mushroom Houses. A. C. Davis* and H. D.
Young. Jour. Econ. Ent., v. 27, no. 2, p. 518-525, Apr. 1934.

217. Lonchocarpic Acid, a New Compound from a Species of Lonchocarpus.
Howard A. Jones. Jour. Amer. Chem. Soc., v. 56, no. 5, p. 1247-
1248, May 1934.

218. Insecticides and Fungicides. R. C. Roark. Ann. Survey of American
Chemistry, vol. 8, 1933, p. 221-242, May 1934.





59 -

Index
No.
219. Colorimetric Method for Determination of Rotenone. C. R. Gross and
C. M. Smith. Jour. Assoc. Off. Agr. Chem., vol. 17, no. 2, p. 336-
339. May 1934.

220. Synthesis of 8-Isoamyl-7-methoxycoumarin (Dihydro-osthol) H. L.
Haller and Fred Acree, Jr. Jour. Amer. Chem. Soc., v. 56, no. 6,
p. 1389-1390, June 1934.

221. Devil's Shoestring (Cracca virginiana L., A Potential Source of
Rotenone and Related Insecticides, R. C. Roark. Mimeographed, 12
pp., June 1934.

222. Base Exchange Reactions of Bentonite and Salts of Organic Bases.
C. R. Smith. Jour. Amer. Chem. Soc., v. 56, no. 7, p. 1561-1563,
July 1934.

223, Rotenone. XXIX. The Isomerism of the Rotenolones. F. B. LaForge
and H. L. Haller. Jour. Amer. Chem. Soc., v. 56, no. 7, p. 1620-
1625, July 1934.

224. Oil Retention, Oil-Emulsifier Ratio, and Oil-Water Ratio as Affect-
ing the Insecticidal Efficiency of Emulsions. A. W. Cressman* and
Lynn H. Dawsey. Jour. Agr. Research, v. 49, no. 1, p. 1-19, July
1, 1934.

225. An Investigation of Solvents for the Removal of Lead Arsenate Res-
idues from Fruits. R. H. Carter. Jour. Econ. Ent., v. 27, no. 4,
p. 848-853, Aug. 1934.

226. Solvents for Cryolite. R. H. Carter. Jour. Econ. Ent., v. 27, no.
4, p. 863, Aug. 1934.

227. Semimicro Determination of Halogens in Organic Compounds. E. P.
Clark. Jour. Assoc. Off. Agr. Chem., vol. 17, no. 3, p. 483-487,
Aug. 1934.

228. Preparation of Acetphenetidin from p-Aminoacetanilid. H. L. Haller
and George L. Keenan.* Jour. Assoc. Off. Agr. Chem., v. 17, no. 3,
p. 512-516, Aug. 1934.

229. Some Physical Constants of Anabasine. 0. A. Nelson. Jour. Amer
Chem. Soc., v. 56, no. 9, p. 1989-1990, Sept. 1934.

230. A Differential Pressure Control Mechanism for Vacuum Distillation.
S. Palkin* and 0. A. Nelson. Indus. and Engin. Chem. Anal. Ed..
v. 6, no. 5, p. 386-387, Sept. 15, 1934.

231. Rotenone. XXX. The Non-Crystalline Constituents of Derris Root.
H. L. Haller and F. B. LaForge. Jour. Amer. Chem. Soc., v. 56.
no. 11, p. 2415-2419, Nov. 1934.






- 60 -


Index
No.
232. Rotenone. XXXI. The Synthesis of 2-Hydroxy-4,5-dimethoxyphenyl-
acetic Acid. L. E. Smith and F. B. LaForge. Jour. Amer. Chem.
Soc., v. 56, no. 11, p. 2431, Nov. 1934,

233. Insecticidal Tests of Synthetic Organic Compounds Chiefly Tests
of Sulfur Compounds Against Culicine Mosquito Larvae. F. L. Camp-
bell,* W. N. Sullivan,* L. E. Smith and H. L. Haller. Jour. Econ.
Ent., v. 27, no. 6, p. 1176-1185, Dec. 1934.

234. Croton Resin. I. Toxicity Studies Using Goldfish. J. R. Spies.
Jour. Amer. Chem. Soc., v. 57, no. 1, p. 180-182, Jan. 1935.

235. Croton Resin. II. The Toxic and Vesicant Action of Certain of Its
Derivatives. J. R. Spies. Jour. Amer. Chem, Soo., v. 57, no. 1,
p. 182-184, Jan. 1935.

236. Croton Resin. III. The Combined Acids. N. L. Drake and J. R.
Spies. Jour. Amer. Chem. Soc., v. 57, no. 1, p.184-187, Jan. 1935.

237. An Improved Sulphur Burner for Mushroom-House Fumigation. A. C.
Davis* and H. D. Young. Mimeographed, E-332, 2 pp., illus., Jan.
1935.

238. Recent Advances in the Knowledge of Derris and Cube. R. C. Roark.
Soap, v. 11, no. 2, p. 97, 99, 105, 107, Feb. 1935.

239. Advantages and Limitations of Organic Insecticides. R. C. Roark
Jour. Econ. Ent., v. 28, no. 1, p. 211-215, Feb. 1935.

240. Recent Developments in Insecticide Research. R. C. Roark. Proc.
5th Pacific Sci. Cong. Canada, 1933. 5: 3405-3410. Toronto. 1934.
[This article was prepared in April 1933. The publication was re-
ceived by the Department Library in March 1935.]

241. Recovery of Silver and Iodine from Silver Iodide. J. R. Spies.
Indus. and Engin. Chem. Anal. Ed., v. 7, no. 2, p. 118-119, March
15, 1935.

242. Spray Residue Removal from Apples. M. H. Haller,* J. H. Beaumont,*
C. R. Gross and H. W. Rusk. Univ. of Md. Agr. Expt. Sta. Bull
No. 368, p. 121-136, Sept. 1934. [Apr. 1935]

243. d-Ribose from the Croton Bean. J. R. Spies with N. L. Drake.
Jour. Amer. Chem. Soc., v. 57, no. 4, p. 774, Apr. 1935.

244. What is Cube? R. C. Roark. Soap, v. 11, no. 4, p.95, 97, 99,
Apr.1935.






61 -

Index
No.
245. Relations Between Chemical Composition and Insecticidal Effective-
ness of Rotenone-Bearing Plants. H. A. Jones, F. L. Campbell* and
W. N. Sullivan.* Jour. Econ. Ent., v. 28, no. 2, p. 285-292, Apr.
1935.

246. Sulfur Fumigation for the Control of Mushroom Pests. A. C. Davis*
and H. D. Young. Jour. Econ. Ent., v. 28, no. 2, p. 459-465, Apr.
1935.

247. References to the Use of Ethylene Oxide for Pest Control. H. D
Young and R. L. Busbey. Multigraphed, 16 pp., Apr. 1935.

248. Insecticides and Fungicides. R. C. Roark. Indus. and Engin.
Chem., v. 27, no. 5, p. 530-532, May 1935.

249. Occurrence of Anabasine in Nicotiana Glauca R. Grah. (Solanaceae)
C. R. Smith. Jour.Amer.Chem.Soc., v.57, no.5, p.959-960, May 1935,

250. A List of Organic Sulphur Compounds (Exclusive of Mothproofing
Materials) Used as Insecticides. R. C. Roark and R. L. Busbey.
E-344, Mimeographed, 104 pp., May 1935.

251. Report on Arsenic. C. R. Gross. Jour. Assoc. Off. Agr. Chem.,
v. 18, no. 2, p. 189-191, May 1935.

252, Lead Residues and Their Removal as Influenced by Spray Programs.
M. H. Haller,* J. H. Beaumont,* C. W. Murray and C. C. Cassil.
Proc. Amer. Soc. Hort. Sci. for 1934, v.32, p.179-182, May 1935.

253. Bibliography of' Chloropicrin 1932-1934 (First Supplement to U. S.
Dept. Agr. Misc. Publication 176). R. C. Roark and R. L. Busbey.
E-351, Mimeographed, 15 pp., June 1935.

254. A Review of Non-Chemical United States Patents Issued from 1917 to
1933, Inclusive, Relating to Insect Control. R. C. Roark. Mul-
tigraphed, 4 pp., June 1935.

255. The Preparation of Picrotoxin. E. P. Clark. Jour. Amer. Chem.
Soc., v. 57, no. 6, p. 1111, June 1935.

256. Insecticide Tests to Control the Codling Moth at the Vincennes,
Indiana, Laboratory During 1934. L. F. Steiner,* R. F. Sazama*
and J. E. Fahey. Trans. Ind. Hort. Soc. for Year 1934, p. 66-71.
June 1935.

257. A New Criterion for the Comparison of Toxicity with Respect to
Concentration and Time. W. A. Gersdorff. Jour. Agr. Research,
v. 50, no. 11, p. 881-891, June 1, 1935. [Issued July 1935.1





- 62 -


Index
No.
253. The Quantitative Relationship between the Constitution and Toxicity
of Some Rotenone Derivatives. W. A. Gersdorff. Jour. Agr. Research,
v. 50, no. 11, p. 893-898, June 1, 1935. [Issued July 19351.

259. A Bibliography of Cyanide Compounds Used as Insecticides. 1930.
H. L. Cupples. E-354, Mimeographed, 58 pp., Aug., 1935.

260. Homologs of Paris Green. I. Lower Members of Acetic Acid Series.
F. E. Dearborn. Jour. Econ. Ent., v. 28, no. 4, p. 710-714, Aug.
1935.

?61. Phenothiazine, a Promising New Insecticide. L. E. Smith, F. Munger*
and E. H. Siegler.* Jour. Econ. Ent.,v. 28, no. 4, p. 727-728, Aug.
1935.

262. Determination of Sulfur in Organic Compounds by the Semimicro
Carius Method. E. P. Clark. Jour. Assoc. Off. Agr. Chem., v. 18,
no. 3, p. 476-477, Aug. 1935.

263. Constituents of Pyrethrum Flowers. I. Determination of Pyrethrin
II. H. L. Haller and Fred Acree, Jr. Indus. and Engin. Chem.
Anal. Ed., v. 7, no. 5, p. 343-344, Sept. 15, 1935.

264. Cracca--A Source of Insecticides. A Preliminary Study of Domestic
Species of Devil's Shoestring as Sources of Insecticidal Materials.
H. A. Jones, F. L. Campbell* and W. N. Sullivan.* Soap, v. 11, no.
9, p. 99, 101, 103, 105, 107, 109, Sept. 1935.

265. Constituents of Pyrethrum Flowers. II. Isolation of Pyrethrin
II. F. B. LaForge and H. L. Haller. Jour. Amer. Chem. Soc., v.
57, no. 10, p. 1893-1896, Oct. 1935.

266. Wetting and Spreading Properties of Aqueous Solutions. I. Oleic
Acid-Sodium Hydroxide Mixtures. H. L. Cupples. Indus. and Engin.
Chem., v. 27, no. 10, p. 1219-1222, Oct. 1935.

267. An Investigation of Solvents for the Removal of Insecticidal Flu-
orine Residues from Fruits. R. H. Carter. Jour. Econ. Ent., v.
28, no. 5, p. 829-831, Oct. 1935.

268. A New Chloroarsenate of Calcium. C. M. Smith. Jour. Wash. Acad.
Sci., v. 25, no. 10, p. 435-436, Oct. 15, 1935.

269. Preparation of Spray Solutions from Tobacco. E-361, Mimeographed,
3 pp., Oct. 19351

270. The Toxicity of Optically Active and Inactive Dihydrodeguelins.
W. A. Gersdorff. Jour. Agr. Research, v. 51, no. 4, p. 355-361,
Aug.1935. [Issued Oct. 1935]






63 -

Index
No.
271. Insecticides for Combating Household Pests. R. C. Roark. Exter-
minators Log, v. 3, no. 11, p, 11-13, Nov. 1935. Also published
under the title Household Insecticides. Soap, v. 11, no. 11, p.
101, 103, 117, Nov. 1935.

272. Cyanide Fumigation of Mushroom Houses. A. C. Davis- and H. V.
Claborn. U. S. Dept. Agr. Circ. No. 364, 10 pp., Nov. 1935.

273. The Vacuum Fumigation of Flour Products with Hydrocyanic Acid.
H. D. Young, George B. Wagner,* and R. T. Cotton.* Jour. Econ. Ent.
v. 28, no. 6, p. 1049-1055, Dec. 1935.

274. The Dimorphism of Rotenone. E. L. Gooden and C. M. Smith. Jour.
Amer. Chem. Soc., v. 57, no. 12, p, 2616-2618, Dec. 1935.

275. Wetting and Spreading Properties of Aqueous Solutions. Oleic
Acid-Sodium Carbonate Mixtures. H. L. Cupples. Indus. and Engin.
Chem., v. 28, no. 1, p. 60-62, Jan. 1936.

276. An Improvement on the Gross and Smith Colorimetric Method for
the Determination of Rotenone and Deguelin. L. D. Goodhue. Jour.
Assoc. Off. Agr. Chem., v. 19, no. 1, p. 118-120, Feb. 1936.

277. A Third Index of Patented Mothproofing Materials. R. C. Roark and
R. L. Busbey. Mimeographed, 104 pp., Feb. 1936.

278. The Use of Low Viscosity Mineral Oils in Spray Residue Control.
Edwin Smith,* A Lloyd Ryall,* C. W. Murray and John Cassidy. Proc.
31st Annual Meeting of the Washington State Horticultural Associa-
tion, p. 157-159, 1935. Feb. 1936.

279. Lonchocarpus Species (Barbasco. Cube, Haiari, Nekoe, and Timbo)
Used as Insecticides. R. C. Roark. E-367, mimeographed, 133 pp.,
Mar. 1936.

280. Book Review of "Organic Chemistry" by Howard J. Lucas. H. L
Haller. Cereal Chemistry, v. 13, no. 2, p. 237, Mar. 1936.

281. A Bibliography of Cyanide Compounds Used as Insecticides. 1931,
H. L. Cupples. E-368, mimeographed, 69 pp., Mar. 1936.

282. Constituents of Pyrethrum Flowers. IV. The Semicarbazones of
Pyrethrins I and II and of Pyrethrolone. H. L. Haller and F. B.
LaForge. Jour. Organic Chemistry, v. 1, no. 1, p. 38-51, Mar. 1936.

283. Wetting and Spreading Properties of Aqueous Solutions. Mixtures of
Oleic Acid with Potassium Hydroxide, Potassium Carbonate. and
Ammonia. H. L. Cupples. Indus, and Engin. Chem., Ind. Ed., v. 28,
no. 4, p. 434-436, Apr. 1936.




-64-


Index
No.
284. Comparative Toxicities of Methyl Thiocyanate and Hydrocyanic Acid
to the California Red Scale. F. H. Lathrop,* H. L. Cupples, Julian
Hiley and H. R. Yust.* Jour. Econ. Ent., v. 29, no. 2, p. 410-412,
Apr. 1936.

285. Homologs of Paris Green. II. Higher Members of the Acetic Acid
Series. F. E. Dearborn. Jour. Econ. Ent., v. 29, no. 2, p. 445-
449, Apr. 1936.

286. Nicotine Peat A New Insoluble Nicotine Insecticide. L. N. Mark-
wood. Indus. and Engin. Chem., Ind. Ed., v. 28, no. 5, p. 561-563,
May 1936.

287. A New Water-Soluble Nicotine Insecticide--Nicotine Humate. L. N.
Markwood. Indus. and Engin. Chem., Ind. Ed., v. 28. no. 6, 648-649,
June 1936.

288. A Bibliography of Cyanide Compounds Used as Insecticides, 1932.
H. L. Cupples. E-381, Mimeographed, 74 pp., June 1936.

289. Derris and Cube. Approximate Chemical Evaluation of Their Toxicity.
Howard A. Jones and C. M. Smith. Soap, v. 12, no. 6, p. 113,
115. 117, June 1936.

290. The Occurrence of Quebrachite in the Stems of Haplcph ton cimicidum.
E. P. Clark. Jour. Amer. Chem. Soc., v. 58, no. 6, p. 1009-1010.
June 1936.

291. Constituents of Pyrethrum Flowers. V. Concerning the Structure of
Pyrethrolone. F. B. LaForge and H. L. Haller. Jour. Amer. Chem.
Soc., v. 58, no. 6, p. 1061, June 1936.

292. Determination of the Less Refined Mineral Oils on Leaf Surfaces
After Spraying. L. H. Dawsey. Jour, Agr. Research, v. 52, no. 9,
p. 681-690, May 1, 1936. Issued June 1936.

293. Insecticides and Fungicides. R. C. Roark. Ann. Survey of American
Chemistry, v. 10, 1935, p. 253-279, June 1936.

294 Fumigation of Flour Mills with Hydrocyanic Acid Gas. R. T. Cotton,*
H. D. Young and George B. Wagner.* Jour. Econ. Ent., v. 29, no. 3,
p. 514-523, June 1936.

295. Laboratory Tests of Phenothiazine Against Codling Moth Larvae.
E, H. Siegler,* F. Munger* and L. E. Smith. Jour. Econ. Ent.,
v. 29, no. 3, p. 532-537, June 1936.

296. Relative Toxicity of Some Optically Active and Inactive Rotenone
Derivatives to Culicine Mosquito Larvae. David E. Fink* and H. L.
Haller. Jour. Econ. Ent., v. 29, no. 3, p. 594-598, June 1936.






65 -

Index
No.
297. Constituents of Pyrethrum Flowers. III. The Pyrethrin Content of
Fresh Flowers. Fred Acree, Jr., P. S. Schaffer and H. L. Haller.
Jour. Econ. Ent., v. 29, no. 3, p. 601-605, June 1936.

298. Tests of Possible Substitutes for Hydrocyanic Acid in Fumigation of
California Red Scale. H. L. Cupples, H. R. Yust* and Julian Hiley.
Jour. Econ. Ent., v. 29, no. 3, p. 611-618, June 1936.

299. The Comparative Insecticidal Efficiency Against the Camphor Scale of
Spray Oils with Different Unsulphonatable Residues. A. W. Cressman*
and Lynn H. Dawsey. Jour. Agr. Research, v. 52, no. 11, p. 865-878,
June 1, 1936. Issued July, 1936.

300. Research to Find Substitutes for Lead Arsenate. R. C. Roark. Conn.
Pomological Society Proc. 45th Annual Meeting Dec. 10-13, 1935,
v. 38, p. 159-165. 1935. (Rec'd. in Dept. Library July 20, 1936).

301. The Relative Efficiency of Certain Lead Arsenate Spray Treatments.
L. F. Steiner,* R. F. Sazama,* J. E. Fahey and H. W. Rusk. Indiana
Horticultural Society Trans. for Year 1935. (Rpt. of 75th Annual
Meeting Jan. 21-23, 1936). p. 38-43. (Rec'd. in Dept. Library
July 20, 1936.)

302. Pyrethrins in the Field Daisy? An Investigation of the Common Field
Daisy for Pyrethrins or Other insecticidal Properties. F. Acree,
Jr., and F.B. LaForge. Soap, v.12, no.8, p.109,111, Aug. 1936.

303. Toxicity of Certain Azo Compounds to Mosquito Larvae. D. E. Fink*
and D. L. Vivian. Jour. Econ. Ent., v. 29, no. 4, p. 804, Aug.
1936.

304. Toxicity of Certain Organic Compounds to Culicine Mosquito Larvae.
D. E. Fink* and L. E. Smith. Jour. Econ. Ent., v. 29, no. 4, p.
804-805, Aug. 1936.

305, Lead Content of Chewing Tobaccos and Snuffs, C. C. Cassil and C. M,
Smith. Amer. Jour. Public Health, v. 26, no. 9, p. 901-904, Sept.
1936.

306. A Bibliography of Nicotine. Part I. Chemistry of Nicotine. R. L.
Busbey and N. E. McIndoo*. E-384, Mimeographed, 257 pp., Sept.
1936.

307. Constituents of Pyrethrum Flowers. VI. The Structure of Pyreth-
rolone. F. B. LaForge and H. L. Haller. Jour. Amer. Chem. Soc..
v. 58, no. 9, p. 1777-1780, Sept. 1936.

308. A Sensitive Thermoregulator. L. D. Goodhue. Indus. and Engin.
Chem., Anal. Ed., vol. 8, no. 5, p. 387, Sept. 15, 1936.





- 66 -


Index
No.
309. The Machinery-Piping System of Flour-Mill Fumigation. Geo. B.
Wagner,* R. T. Cotton* and H. D. Young. E-396, Multigraphed, 8 pp,
12 figs., Oct. 1936.

310. Helenalin. I. Helenalin, the Bitter Sternutative Substance Occur-
ring in Helenium autumnale. E. P. Clark. Jour. Amer. Chem. Soo.,
v. 58, no. 10, p. 1982-1983, Oct. 1936.

311. The Fluorine Compounds as Insecticides. A Monograph with Annotated
Bibliography. R. H. Carter. Jour. Econ. Ent., v. 29, no. 5, p.
1022-1023, Oct. 1936.

312. Potential New Insecticides. L. E. Smith, E. H. Siegler* and F.
Munger.* Jour. Econ. Ent., v. 29, no. 5, p. 1027, Oct. 1936.

3i3. Portable Rack for Kjeldahl Flasks. H. W. Rusk. The Chemist Analyst,
v. 25, no. 4, p. 92-93, Oct. 1936.

314. Eook review of "Introduction to Theoretical Chemistry" by William
Bell Mildrum and Frank Thomson Gucker. 0. A. Nelson. Jour. Assoc.
Off. Agr. Chem., v. 19, no. 4, p. 671, Nov. 15, 1936.

315. The Particle Size of Insecticidal Dusts. A New Differential Mano-
meter-Type Sedimentation Apparatus. L. D. Goodhue and C. M. Smith.
Indus. and Engin. Chem., Anal. Ed., v. 8, no. 6, p. 469-472, Nov.
15, 1936.

316. Seji-Microdetermination of Acetyl Especially in O-Acetyl Compounds.
E. P. Clark. Indus. and Engin. Chem., Anal. Ed., v. 8, no. 6,
p. 487-488, Nov. 15, 1936.

317. The Solubility of Nicotine oSilicotungstate in Solutions of Dilute
Hydrochloric Acid. J. R. Spies. Jour. Amer. Chem. Soc., v. 58.
no. 12, p. 2386-2388, Dec. 1936.

31G. Beta-Octyl Thiocyanate. W. Gordon Rose and H. L. Haller. Jour.
Amer. Chem. Soc., v. 58, no. 12, p. 2648-2649, Dec. 1936.

319. A Bibliography of Nicotine. Part II. The Insecticidal Uses of
Nicotine and Tobacco. N. E. McIndoo,* R. C. Roark and R. L. Busbey.
E-392. Mimeographed in 3 sections (Section 1, 198 pp.; Section 2.
p. 199-358; and Section 3, p. 359-628), Jan. 1937.

320. Determination of Small Quantities of Nicotine by a Silicotungstic
Acid Micromethod. J. R. Spies. Indus. and Engin. Chem., Anal.
Ed., v. 9, no. 1, p. 46, 47, Jan. 15, 1937.

321. The Use of Phenothiazine as an Insecticide. L. E. Smith. E-399,
Mimeographed, 11 pp., Jan. 1937.





67 -

Index
No.
322. The Optical Rotatory Power of Extracts of Derris and Cube Roots.
H. A. Jones. Jour. Agr. Research, v. 53, no. 11, p. 831-839, Dec.
1, 1936 (issued Jan. 1937).

323. Relative Toxic Action of Phenol and Phenyl Mercaptan. When the Gold-
fish is Used as the Test Animal. W. A. Gersdorff. Jour. Agr. Re-
search, v. 53, no. 11, p. 841-847, Dec. 1, 1936 (issued Jan. 1937).

324. Homologs of Paris Green. III. Members of the Oleic and Linoleic
Acid Series. F. E. Dearborn. Jour. Econ. Ent., v. 30, no. 1,
p. 140-143, Feb. 1937.

325. Variability in Lead Residues on Apples. M. H. Haller,* C. C.
Cassil and Edwin Gould.* Jour. Econ. Ent., v. 30, no. 1, p. 174-
179, Feb. 1937.

326. Pyrethrins in Fresh Pyrethrum Flowers. H. L. Haller. Jour. Econ.
Ent., v. 30, no. 1, p. 210-211, Feb. 1937.

327. Tephrosia as an Insecticide A Review of the Literature. R. C.
Roark. E-402, Mimeographed, 165 pp., Feb. 1937.

328. A Crystalline Compound of Semicarbazide and Semicarbazide Hydroch-
loride. H. L. Haller and F. B. LaForge. Jour. Amer. Chem. Soc.,
v. 59, no. 4, p. 760, Apr. 1937.

329. The Solubility of Certain Semicarbazones in Dilute Hydrochloric
Acid. F. B. LaForge and H. L. Haller. Jour. Amer. Chem. Soc.,
v. 59, no. 4, p. 760-761, Apr. 1937.

330. The Relative Quantities of Oil Deposited Upon Paraffin-Coated Plates
and Upon Plant Foliage by Oil Sprays. L. H. Dawsey, A. W. Cressman*
and J. Hiley. Jour. Agr. Research, v. 54, no. 5, p. 387-398,
March 1, 1937. [Issued April, 1937].

331. Toxicity of Phenothiazine Derivatives to Culicine Mosquito Larvae.
P. S. Schaffer, H. L. Haller and D. E. Fink.* Jour. Econ. Ent.,
v. 30, no. 2, p. 361-363, Apr. 1937.

332. Principal Optical and Physical Properties of the Carbon Tetrachlor-
ide Solvate of Rotenone. E. L. Gooden and C. M. Smith. Jour. Amer.
Chem. Soc., v. 59, no. 5, p. 787-789, May 1937.

333. Quassin. I. The Preparation and Purification of Quassin and Neo-
quassin, with Information Concerning their Molecular Formulas. E.P.
Clark. Jour. Amer. Chem. Soc., v. 59, no. 5, p. 927-931, May 1937.

334. Determination of Rotenone in Derris and Cube. Crystallization from
Extracts. Howard A. Jones. Indus. and Engin. Chem., Anal. Ed..
vol. 9. no. 5, p. 206-210, May 15, 1937.







- 68 -


Index
"No.
335. Relative Toxicity of the Cresols as Demonstrated by Tests with
Carassius auratus. W. A. Gersdorff. Jour. Agr. Research, v. 54,
no. 6, p. 469-478, March 15, 1937. [Issued May, 1937.]

336. Recent Advances in the Vacuum Fumigation of Cereal Products with
Certain Fumigants. R. T. Cotton,* Geo. B. Wagner* and H. D. Young.
E-405, Multigraphed, 7 pp., 3 figs., May 1937.

337. The Arsenates of Manganese as Insecticides (A Review of the Lit-
erature). F. E. Dearborn. E-408, Mimeographed, 27 pp., May 1937.

338. Report on Arsenic. C. C. Cassil. Jour. Assoc. Off. Agr. Chem.,
v. 20, no. 2, p. 171-178, May 1937.

339. The Decomposition of 2-Fluorenediazonium Chloride and 2-Fluorenone-
diazonium Chloride in Acetic Acid. H. V. Claborn and H. L. Haller.
Jour. Amer. Chem. Soo., v. 59, no. 6, p. 1055-1056, June 1937.

340. Constituents of Pyrethrum Flowers. VII. The Behavior of the Py-
rethrins on Hydrogenation. H. L. Haller and F. B. LaForge. Jour.
Organic Chemistry, v. 2, no. 1, p. 49-55, Mar. 1937. [Issued June,
1937].

341. Constituents of Pyrethrum Flowers. VIII. The Presence of a New
Ester of Pyrethrolone. F. B. LaForge and H. L. Haller. Jour.
Organic Chemistry, v. 2, no. 1, p. 56-61, March, 1937. [Issued
June, 1937.]

342. Croton Resin. IV. The Petroleum-Ether-Insoluble Acids. J. R.
Spies. Jour. Organic Chemistry, v. 2, no. 1, p. 62-67, Mar. 1937.
[Issued June 1937]

343. Particle Size of Commercial Calcium Arsenates by Sedimentation
Analysis. L. D. Goodhue. Jour. Econ. Ent., v. 30, no. 3, p.
466-474, June 1937.

344. An Examination of Commercial Calcium Arsenates. 0. A. Nelson and
C. C. Cassil. Jour. Econ. Ent., v. 30, no. 3, p. 474-478, June
1937.

345. An Insect that Breathes Through Its Nose. R. C. Roark. Jour. Econ.
Ent., v. 30, no. 3, p. 522-527, June 1937.

346. Oxygen as a Factor in Vacuum Fumigation. R. T. Cotton,* G. B.
Wagner* and H. D. Young. Jour. Econ. Ent., v. 30, no. 3, p. 560,
June 1937.







69 -
Index
No.
347. Relationship of Grains of Spray Residue per Pound of Apple to
Micrograms per Square Centimeter of Surface A Conversion Table.
H. W. Rusk. Hoosier Horticulture, vol. 19, no. 7, p. 109-112, July
1937. [Reprinted in Trans. Indiana Horticultural Society for 1937,
pp. 120-122 Rec'd. in Dept. Library Aug. 1938.]

348. Chemical Studies of Spray Deposits. J. E. Fahey and H. W. Rusk.
Indiana Horticultural Society Transactions for the year 1936, being
a Report of the 76th Annual Meeting held January, 1937, p. 85-90,
[Rec'd. by Department Library July 27, 1937.]

349. Wetting and Spreading Properties of Aqueous Solutions. Mixtures of
Sodium Hydroxide with n-Caproic, n-Caprylic, n-Capric. Lauric,
Myristic, and Palmitic Acids, H. L. Cupples. Ind. Eng. Chem.,
Ind. Ed., vol. 29, no. 8, pp. 924-926, August 1937.

350. Laboratory Apparatus for Fumigation with Low Concentrations of
Nicotine With Studies on Aphids. H. H. Richardson* and R. L.
Busbey. Jour, Econ. Ent., vol. 30, no. 4, p, 576-582, August 1937.

351. Semicommercial Manufacture of Nicotine Peat. L. N. Markwood. Jour.
Econ. Ent., vol. 30, no. 4, p. 648-651, August 1937.

352. Chemical and Insecticidal Tests of Samples of Tephrosia toxicaria.
H. A. Jones and W. N. Sullivan.* Jour. Econ. Ent., vol. 30, no. 4,
p. 679-680, August 1937.

353. Constant-Temperature Bath for Molecular Stills. 0. A. Nelson and
H. L, Haller, Ind, Eng. Chem., Anal. Ed., vol. 9, no. 8, p. 402,
August 1937.

354. Report on Fluorine Compounds. R. H. Carter. Jour. Assoc. Off.
Agr. Chem., vol. 20, no. 3, p. 394, August 1937.

355. Constituents of Pyrethrum Flowers. IX. The Optical Rotation of
Pyrethrolone and the Partial Synthesis of Pyrethrins. H. L. Haller
and F. B. LaForge. Jour. Amer. Chem. Soc., vol. 59, no. 9, p.
1678-1681, September 1937.

356. Occurrence of 1-Nornicotine in Nicotiana sylvestris. C. R. Smith.
Jour, Econ. Ent., vol. 30, no. 5, p. 724-727, October, 1937.

357. Composition of Paris Greens Manufactured During 1936. F. E. Dear-
born. Jour. Econ. Ent., vol. 30, no. 5, p. 804, October 1937.

358. Heavier-Than-Air Fumigants and Their Relation to Methods of Fumiga-
tion for Insect Control. R.T. Cotton*, G.B. Wagner*, and H.D. Young,
The National Grain Jour,, vol. 21, no. 11, p.10-12, October 1937.








-70 -


Index
No.
359. A Statistical Study of the Sampling and Analytical Errors Encountered
in Analyzing Apples for Lead Spray Residues. C. M. Smith and
C. C. Cassil. Jour. Assoc. Off. Agr. Chem., vol. 20, no. 4, p.
617-622. November 1937.

360. Book Review of "Qualitative Analysis and Chemical Equilibrium" by
T. R. Hogness and W. C. Johnson. 0. A. Nelson, Jour. Assoc. Off.
Agr. Chem., vol. 20, no. 4, p. 656, November 1937.

361. The Problem of Controlling Insects in Flour Warehouses. R. T.
Cotton,* G. B. Wagner,* and H. D. Young, American Miller, vol. 65,
no. 11, p. 22, 24, 26, 79, November 1937.

362. The Determination of Acetyl, Especially in O-Acetyl Compounds. E. P.
Clark. Ind. Eng. Chem., Anal. Ed., vol. 9, no. 11, p. 539, November
1937.

363. Calcium Arsenates. An Investigation into the Three-Component System
Calcium Oxide-Arsenic Oxide-Water. 0. A. Nelson and M. M. Haring*,
Jour. Amer. Chem. Soc., vol. 59, no. 11, p. 2216-2223, November
1937.

364. Experiments with Certain Copper Compounds as Bunt Fungicides. 0. A.
Nelson and R. W. Leukel*, U. S. Dept. Agr. Circ. #452, 8 pp.,
November 1937.

365. Quassin. II. Neoquassin. E. P. Clark. Jour. Amer. Chem. Soc.,
vol. 59, no. 12, p. 2511-2514, December 1937.

366. The Solubility of Rotenone. II. Data for Certain Additional Sol-
vents. H. A. Jones and S. Love. Jour. Amer. Chem. Soc., vol. 59,
no. 12, p. 2694-2696, December 1937.

367. A Motor-Driven Telescoping Stirrer for Use with an Insecticide
Spraying Apparatus. L. D. Goodhue and E. H. Siegler.* Bureau of
Entomology and Plant Quarantine ET-114, 1 p., 1 fig. Multigraphed.
December 1937.

368. Some Physical Properties of Commercial Paris Greens. L. D. Goodhue
and E. L. Geoden. Jour. Econ. Ent., vol. 30, ne. 6, p. 913-917.
December 1937.

369. Homologs of Paris Green. IV. Insecticides Prepared from Animal and
Vegetable Oils. F. E. Dearborn, Jour. Econ. Ent., vol. 30, no. 6.
p. 958-962, December 1937.





71 -

Index
No.
370. Constituents of Pyrethrum Flowers. X. Identification of the Fatty
Acids Combined with Pyrethrolone. F. Acree Jr. and F. B. LaForge.
Jour. Organ. Chem., vol. 2, no. 4, p. 308-313, Sept. 1937. (Rec'd.
in Insecticide Div. in Jan. 1938.)

371. Improvements in Determination of Oil Deposit on Sprayed Foliage.
L. H. Dawsey and J. Hiley. Jour. Agr. Res., vol. 55, no. 9, p.
693-701, Nov. 1, 1937. (Rec'd. in Insecticide Div. in Jan. 1938.)

372. Derris versus Cube. Is Cube Equal to Derris as an Insecticide?
R. C. Roark. Soap, vol. 14, no. 1, p. 111-113, 120, Jan. 1938.

373. Determination of Rotenone in Derris and Cube. II. Extraction from
the Root. H. A. Jones and J. J. T. Graham.* Ind. Eng. Chem., Anal.
Ed. vol. 10, no. 1, p. 19-23, Jan. 1938.

374. Turbidimetric Titration of Small Amounts of Nicotine by the Use of
a Photo-electric Cell. L. D. Goodhue. Ind. Eng. Chem., Anal. Ed.,
vol. 10, no. 1, p. 52-54, Jan. 1938.

375. Agnihotra or an Ancient Process of Fumigation, by Satya Prakash.
Book Review by R. C. Roark. Ind. Eng. Chem., vol. 16, no. 2, p. 68,
Jan. 20, 1938. News Edition.

376. Analysis of Commercial Phenothiazine Used as an Insecticide. L. E.
Smith. Indus. Engin. Chem., Anal. Ed., vol. 10, no. 2, p. 60.,
Feb. 15, 1938.

377. Determination of Rotenone in Derris and Cube III. An Improved
Crystallization Method. H. A. Jones and J. J. T. Graham. Jour
Assoc. Off. Agr. Chem. 21, No. 1, p. 148-151. February 1938.

378. Determination of Nicotine on Apples Sprayed with Nicotine Bentonite.
L. N. Markwood. Jour. Assoc. Off. Agr. Chem. V. 21, No. 1, p. 151-
155. February 1938.

379. Wetting Properties of Triethanolamine Oleate. H. L. Cupples.
Jour. Econ. Entom., vol. 31, no. 1, p. 68-79, Feb. 1938.

380. Effect of Insect Attack on the Rotenone Content of Stored Cube Root.
H. A. Jones. Jour. Econ. Entom., vol. 31, no. 1, p. 127, Feb. 1938.

381. Toxicity Tests with Synthetic Organic Compounds against Culicine
Mosquito Larvae. D. E. Fink,* L. E. Smith, D. L. Vivian, and H. V.
Claborn. Bureau of Entomology and Plant Quarantine publication
E-425, mimeo., 34 pp., March, 1938.

382. Constituents of Pyrethrum Flowers. XI. Chrysanthin. W. G. Rose and
H. L. Haller. Jour. Organ. Chem., vol. 2, no. 5, p. 484-488, Nov.
1937. [Received in Insecticide Div. in April 1938.1







-72 -
Index
No.
383. A List of Proprietary Detergents, Wetting Agents, and Emulsifying
Agents. H. L. Cupples. Bureau of Entomology and Plant Quarantine
publication E-426, 24 pp., April, 1938.

384. Tank-Mix Nicotine-Bentonite for Control of the Codling Moth. L. F.
Steiner* and R. F. Sazama,* and J. E.Fahey and H. W. Rusk. Bureau
of Entomology and Plant Quarantine publication E-428, multi., 4
pp., April, 1938. (Revised January,1939.)

385. Toxicity of Hydrogenated Pyrethrins I and II to the Housefly. H. L.
Haller and W. N. Sullivan.* Jour. Econ. Ent., vol. 31, no. 2,
p. 276-277, April, 1938.

386. Complexity of Calcium Arsenate as Revealed by Chemical Analysis of
Fractions of Different Particle Size. Lyle D. Goodhue and C. C.
Cassil. Jour. Econ. Ent., vol. 31, no. 2, p. 278-280, April, 1938.

337. Organic Compounds Highly Toxic to Codling Moth Larvae. L. E. Smith,
E. H. Siegler,* and F. Munger.* Jour. Econ. Ent., vol. 31, no. 2,
p. 322-323, April 1938.

388. The Toxicity of Phenothiazine and Some of its Oxidation Products in
Experiments with Carassius auratus. W. A. Gersdorff and H. V.
Claborn. Jour. Agr. Res., vol. 56, no. 4, pp. 277-282, Feb. 15,
1938. [Received in Insecticide Div. in May 1938.]

389. Quassin. III. Picrasmin. E. P. Clark. Jour. Amer. Chem. Soo..
vol. 60, no. 5, p. 1146-1148, May, 1938.

390. Report on Arsenic. C. C. Cassil. J. Assoc. Off. Agr. Chem., vol.
21, no. 2, p. 198-203, May, 1938.

391. Determination of Small Quantities of Antimony in Tartar Emetic Spray
Residues. J. Davidson,* G. N. Pulley,* and C. C. Cassil. J.
Assoc. Off. Agr. Chem., vol. 21, no. 2, p. 314-318, May, 1938.

392. Fungicides vs. Insecticides. L. E. Smith. Ind. Eng. Chem., News
Ed., vol. 16, no. 10, p. 306, May 20, 1938.

393. Organic Insecticides. F. B. LaForge and L. N. Markwood. Annual
Review of Biochemistry, vol. VII, 1938, p. 473-490. [Received in
Dept. Library June, 1938.]

394. Insecticides and Fungicides, 1918-38. R. C. Roark. Chemical In-
dustries, vol. 42, no. 6, part 1, pp. 636, 637, 639, June, 1938.

395. Evaluating Derris and Cube: The Question of Total Extractive Con-
tent. H. A. Jones and W. N. Sullivan.* Jour. Econ. Ent., vol. 31,
no. 3, pp. 400-405, June 1938.






-73 -

Index
No.
396. The Particle Size of Commercial Insecticidal Sulfurs as Determined
by Sedimentation Analysis. L. D. Goodhue. Jour. Econ. Ent., vol.
31, no. 3, p. 410-414, June 1938.

397. An Automatic Continuous Percolator. M. S. Schechter and H. L.
Haller, Ind. Engin. Chem., Anal. Ed., vol. 10, no. 6, p. 328, June
15, 1938.

398. Removal of Lead Spray Residues from Apples Grown in the Shenandoah-
Cumberland Valley. M. H. Haller, C. C. Cassil, C. W. Murray. J. H.
Beaumont, and Edwin Gould. U. S. Dept. Agr. Tech. Bul. No. 622,
31 pp. July 1938.

399. Constituents of Pyrethrum Flowers, XII. The Nature of the Side-
Chain of Pyrethrolone. F. B. LaForge and H. L. Haller. Jour.
Organic Chemistry, vol. 2, no. 6, p. 546-559. Jan. 1938. [Rec'd.
in Insecticide Div. in July, 1938.]

400. Determination of Small Quantities of Methyl Bromide in Air. R. L.
Busbey and N. L. Drake. Ind. Engin. Chem., Anal. Ed.. vol. 10, no.
7, pp. 390-392, July 15, 1938.

401. A Modification of the Markley Melting Point Apparatus. M. S.
Schechter and H. L. Haller. Ind. Engin. Chem., Anal. Ed., vol. 10.
no. 7, p. 392, July 15, 1938.

402. Percent Larvicidal Efficiency and Spray Deposits in Relation to
Growth Rainfall and Timing of Cover Sprays on Jonathan. L. F.
Steiner,* J. E. Fahey. R. F. Sazama,* and H. W. Rusk. Trans. Indiana
Horticultural Society for 1937, pp. 88, 89. [Rec'd in Dept. of Agr.
Library in Aug. 1938.]

403. Methods of Analysis of Impregnated Wood for the Preservative Elements
Copper, Mercury, Zinc, Arsenic and Fluorine. R. H. Carter, R. G.
Capen, and C. C. Cassil. Proc. Amer. Wood-Preservers' Assoc. vol.
34, pp. 78-82. [Rec'd in Dept. of Agr. Library in Aug. 1938.]

404. Discussion of the Term "Derris Resinate." R. C. Roark. Jour.
Econ. Ent. vol. 31, no. 4, p. 545, August 1938.

405. Recent Developments in Codling Moth Research. L. F. Steiner,* J. E.
Fahey and R. F. Sazama.* Proc. Amer. Pomological Society, 53rd
Convention, Dec. 8-10, 1937, pp. 129-141. [Rec'd in Dept. Agr.
Library August, 1938.]

406. Knockdown in Fly Sprays. Comparison of Toxicities of Pyrethrins
I and II as Determined by Method for Knockdown and Mortality.
W. N. Sullivan,* H.L. Haller, E. R. McGovran,*andG. L. Phillips.*
Soap, vol. 14, no. 9, pp. 101, 103, 105, September, 1938.






-74 -


Index
No.
407. Removal of Nicotine-Bentonite Spray Residues from Apples at Harvest.
Jack E. Fahey, Harold W. Rusk, L. F. Steiner and R. F. Sazama.
Hoosier Horticulture, vol. 20, no. 9, pp. 138-141, September, 1938.
[Reprinted in Trans. Indiana Hort. Soc. for 1938, pp. 114-116 (Re-
ceived in U. S. Dept. Agr. Library in May 1939).]

403. The Preparation of Amyl Salicylates. A. F. Freeman and H. L. Haller.
Jour. Amer. Chem. Soo., vol. 60, no. 9, pp. 2274, 2275, September,
1938.

409. Abstracts of Foreign and Domestic Patents Relating to Derris, Lon-
chocarpus, Tephrosia, and Rotenone. R. C. Roark. Bur. Entomology &
Plant Quarantine E-446. Mimeo. 69 pp. (Aug. 1938). Received in
Insecticide Div. in Sept. 1938.

410. Method for Debasing New Jersey Peat. L. N. Markwood. Ind. Eng.
Chem., Ind. Ed., vol. 30, no. 10, p. 1199, Oct. 1938.

411. The Arsenates of Magnesium as Insecticides (A Review of the Lit-
erature). F. E. Dearborn. Bureau of Entomology and Plant Quaran-
tine Publ. E-451, Mimeo. 42 pp., October 1938.

412. Toxicity of Ether-Soluble and Ether-Insoluble Fractions of Commercial
Phenothiazine to Certain Insects. L. E. Smith. Jour. Econ. Ent.,
vol. 31, no. 5, p. 631, October 1938.

413. Preparation of Pyrethrins. Isolation of Pyrethrin II -- Effect of
Aqueous Extraction on Pyrethrin Content of Pyrethrum. M. S. Schech-
ter and H. L. Haller. Soap, vol. 14, no. 11, pp. 101, 103, Novem-
ber, 1938.

414. References to Reviews and Popular Articles on Derris. R. C. Roark.
Bureau of Entomology and Plant Quarantine Publ. E-457, Mimeo. 28 pp.
October, 1938. [Received in Insecticide Div. November, 1938.1

415. Effect of the Replacement of Oxygen with Sulphur in the Cresol
Molecule on Toxicity to Goldfish. W. A. Gersdorff. Protoplasma,
pp. 199-206, vol. 31, no. 2, 1938. [Reprints received in Insecti-
cide Div. in Nov. 1938.1

416 Concerning the Dyer Method for the Identification and Determination
of Volatile Fatty Acids. E. P. Clark and Fred Hillig.* Jour. Assoc.
Off. Agri. Chem., vol. 21, no. 4, p. 684-688, Nov. 1938.

417. A Chemical Procedure for Evaluating Spoilage in Canned Fish, Espe-
oially Salmon and Tuna Fish. Fred Hillig* and E. P. Clark. Jour.
Assoc. Off. Agri. Chem., vol. 21, no. 4, p. 688-695, Nov. 1938.





75-

Index
NO-.
418. "An Introduction to Microchemical Methods for Senior Students of
Chemistry," C. L. Wilson. Book Review by E. P. Clark. Jour.
Assoc. Off. Agri. Chem., vol. 21, no. 4, p. 705-706, Nov. 1938.

419. Lonchocarpus (Barbasco, Cube, and Timbo) A Review of Recent
Literature. R. C. Roark. Bureau of Eentomology and Plant Quarantine
Publ. E-453. Mimeo. 174 pp. October, 1938. [Received in Insecti-
cide Division in December, 1938.1

420. Derris Effects of Sunlight and Rain on Derris Deposits as Studied
in the Laboratory. R. D. Chisholm and L. D. Goodhue. Soap, vol. 14,
no. 12, pp. 117, 119, 131, December 1938.

421. The Early History (1848-1918) of the use of Derris as an Insecticide.
R. C. Rcark. Pests, vol. 6, no. 12, pp. 8-10, December 1938.

422. Preparation of Hydriodic Acid Suitable for Alkoxyl and Friedrich-
Kjeldahl Nitrogen Determinations. E. P. Clark. Ind. Engin. Chem.,
Anal. Ed., vol. 10, no. 12, p. 677, December 15, 1938.

423. A Titrimetric Step in Determining Rotenone. H. A. Jones. Ind.
Engin. Chem., Anal. Ed., vol. 10, no. 12, pp. 684-685, December 15,
1938.

424. Replacement of the Diazo Group by the Acetoxy Group. II. The Prepa-
ration of m-Bromophenyl and m-Iodophenyl Acetates. L. E. Smith and
H. L. Haller, Jour. Amer. Chem. Soc., vol. 61, no. 1, pp. 143-144,
Jan. 1939.

425. The Pyrethrin Content of Home-Made Fly Sprays. S. I. Gertler and
H. L, Haller. Soap, vol. 15, no. 1, pp. 93-94, January 1939.

426. A Resume of Insecticide Literature and Patents. R. C. Roark. Soap,
vol. 15, no. 1, pp. 105, 107, 115, January, 1939.

427. Synthetic Organic Compounds Used as Insecticides. R. C. Roark.
Canadian Entomologist, vol. 70, no. 12, pp. 248-253, December 1938.
[Received in Insecticide Div. in January 1939.]

428. How Fumigation Affects Popping Quality of Corn. H. D. Young, R. T.
Cotton* and G. B. Wagner.* Food Industries, vol. 11, no. 1, pp. 14,
56, January, 1939.

429. Agricultural Products as Insecticides. R. C. Roark. Ind. Engin.
Chem., Ind. Ed., vol. 31, no. 2, pp. 168-171, February, 1939.

430. Constituents of Pyrethrum Flowers. XIV. The Structures of the
Enols of Pyrethrolone. H. L. Haller and F. B. LaForge. Jour.
Organic Chem., vol. 3, no. 6, pp. 543-549, January. 1939. [Received
in Insecticide Div. February 1939.1





-76 -


Index
No.
431. A Digest of the Literature Through 1934 Relating to Insecticidal
Spray Residues. R. L. Busbey. Bureau of Entomology and Plant
Quarantine E-463. Mimeo. 221 pp. February 1939.

432. The Use of Fluorine Compounds as Insecticides, A Review with An-
notated Bibliography. R. H. Carter and R. L. Busbey. Bureau of
Entomology and Plant Quarantine E-466. Mimeo. 145 pp. February,
1939,

433. Ch ,icals and Methods Used in Treatments of Trees by Injections, with
Annotated Bibliography. R. H. Carter. Bureau of Entomology and
Plant Quarantine E-467. Mimeo. 25 pp. February, 1939.

434. The History of the Use of Derris as an Insecticide. Part II-The
Period 1919-1928. R. C. Roark. Bureau of Entomology and Plant
Quarantine E-468. Mimeo. 79 pp. February 1939.

435. Toxicity to the Codling Moth Larva of Derivatives of Benzene Con-
taining Halogen and Nitro Groups. E. H. Siegler,* F. Munger* and L. E.
Smith. Jour. Econ. Ent., vol. 32, no. 1, pp. 129-131. February 1939.

436. Crystalline Solvates of Inactive Deguelin. L. D. Goodhue and H. L.
Haller. Jour. Amer. Chem. Soc., vol. 61, no. 2, pp. 486-488.
February 1939.

437. Effect of Particle Size of Some Insecticides on Their Toxicity to
th- odling Moth Larva. E. H. Siegler and L. D. Goodhue, Jour.
Econ. Ent. vol. 32, no. 2, pp. 199-203. April 1939.

438. Insect Pests of Derris. R. C. Roark. Jour. Econ. Ent., vol. 32,
no. 2, pp. 305-309. April 1939.

439. Possible Changes in Ratio of Lead to Arsenious Lxide in Lead Arsen-
ate Residues on Apples. J. E, Fahey and H. W. Rusk. Jour. Econ.
Ent., vol. 32, no. 2, pp. 319-322. April 1939.

440. Sedimentation and Microprojection Methods for Determining Particle-
Size Distribution of Insecticidal Materials. L. D. Goodhue and E.
L. Cooden. Jour. Econ. Ent., vol. 32, no. 2, pp. 334-339. April
1939.

441. Drriis of High Rotenone Content. H. A. Jones. Jour. Econ. Ent.
vol. 32, no. 2, p. 344. April 1939.

442. Derris Stability Effect of temperature and light upon the decom-
position of derris. R. D. Chisholm. Soap, vol. 15, no. 5, p. 103,
105. May, 1939.

443. Recent Progress in the Chemistry of Pyrethrum Flowers. H. L. Haller
and F. B. LaForge. Pests, vol. 7, no. 5, pp. 9, 10. May 1939.







-77 -

Index
_ No.
444. Report on Arsenic. C. C. Cassil. Jour. Assoc. Off. Agr. Chem.,
vol. 22, no. 2, pp. 319-320. May 1939.

445. Tha Photometric Determination of Nicotine on Apples, Without Dis-
tillation. L. N. Markwood. Jour. Assoc. Off. Agr. Chem., vol. 22,
no. 2, pp. 427-436. May 1939.

446, A Rapid Volumetric Micro Method for Determining Arsenic. C. C.
Cassil and H. J. Wichmann. Jour. Assoc. Off. Agr. Chem., vol. 22,
no. 2, pp. 436-445. May 1939.

447. Codling Moth Insecticide Investigations in 1938 at the Vincennes
Laboratory. L. F. Steiner, J. E. Fahey, and S. A. Summerland.
Trans. Indiana Horticultural Society for 1938 (being a Report of the
78th Annual Meeting held in Lafayette, Jan. 10, 11, and 12, 1939,
together with Lectures, etc.) pp. 86-99. [Received in U. S. Dept.
Agr. Library in May 1939.] Also published in Trans. Illinois
Horticultural Society, vol. 72, pp. 439-458 (1938).

448. List of common names used for species of Derris in connection with
insecticidal properties. R. C. Roark. Bureau of Entomology and
Plant Quarantine Publ. E-477. Mult. 18 pp. June 1939.

449. A bibliography of Quassia. R. L. Busbey. Bureau of Entomology and
Plant Quarantine Publ. E-433. Mimao. 56 pp. June 1939.

450. Laboratory spraying and washing apparatus. Robert D. Chisholm.
Bureau of Entomology and Plant Quarantine Publ. ET-149. Multi.
2 pp. 1 illus., June 1939.

451. The effects of neutral copper fungicides on tank-mix nicotine-
bentonite in control of the codling moth. L. F. Steiner* and J. E.
Fahey. Jour. Econ. Ent., vol. 32, no. 3, pp. 365-369. June 1939.

452. Preparation of calcium arsenates of low solubility. 0. A. Nelson,
Jour. Econ. Ent., vol. 32, no. 3, pp. 370-372. June 1939.

453. The Identity of Pyrethrosin with Chrysanthin and Non-identity with
Geigerin. M. S. Schechter and H. L. Haller. Jour. Amer. Chem.
Soo., vol. 61, no. 6, pp. 1607-1609. June 1939.

454. Removal of Phenothiazine Spray Residues from Apples. C. W. Murray
and A. Lloyd Ryall.* Indus. Engin. Chem., News Ed., vol. 17, no. 12,
p. 407. June 20, 1939.

455. Funnel-heating device. L. N. Markwood. Science, vol. 89. no. 2322,
p. 612. June 30, 1939.







- 78 -


Index
No.
456. The Constituents of Certain Species of Helenium. II. Tenulin.
E. P. Clark. Jour. Amar. Chem. Soc., vol. 61, no. 7, pp. 1836-
1840. July 1939.

437. Rotenone Series Compounds A Study of Toxicity to the Housefly of
Optically Active and Inactive Compounds of the Rotenone Series.
W. N. Sullivan*, L. D. Goodhue, and H. L. Haller. Soap and Sanitary
Chemicals, vol. 15, no. 7, pp. 107, 109, 111, 113. July 1939.

458. The Action of Isobutylmagnesium Bromide on 3,4,5-Trimethoxybenzo-
nitrile. By H. L. Haller and P. S. Schaffer. Jour. Amer. Chem.
Soc., vol. 61, no. 8, p. 2175-2177. Aug. 1939.

459. Colorimetric Evaluation of Derris and Cube Roots. H. A. Jones.
Ind. Engin. Chem., Anal. Ed., vol. 11, no. 8, pp. 429-431, Aug.
15, 1939.

460. Effect of the Introduction of the Nitro Group into the Phenol
Molecule on Toxicity to Goldfish. W. A. Gersdorff. Jour. Cellular
and Comparative Physiology, vol. 14, no. 1, pp. 61-71, Aug. 20, 1939.

461. Toxicity of Certain Organic Insecticides to Codling Moth Larvae in
Laboratory Tests. E. H. Siegler,* F. Munger,* and L. E. Smith.
U. S. Dept. Agr. Cir. No. 523, 9 pp., May, 1939. [Received in
Insecticide Div. August 1939.]

462. Determination of Arsenic in Soil Treated with Acid Lead Arsenate.
Louis Koblitsky. Jour. Assoc. Off. Agric. Chem., vol. 22, no. 3,
pp. 630-683, August 1939.

463. Significant Properties of Some Cryolite Materials Offered for
Insecticidal Use. R. H. Carter. Jour. Econ. Ent., vol. 32, no. 4,
p. 490-492, August 1939.

464. Alkaloids in Cube Root. H. A. Jones. Jour. Econ. Ent., vol. 32,
no. 4, p. 596, August 1939.

465. The Removal of Nicotine Spray Residue from Apples. J. F. Cassidy
and Edwin Smith.* Jour. Econ. Ent., vol. 32, no. 4, p. 598, August
1939.

436. Unusual D3velopment of Apple Perennial Canker, Following Application
of Toxic Wound Dressings. E. L. Reeves,* M. A. Yothers,* and C. W.
Murray. Phytopathology, vol. 29, no. 8, pp. 739-743, August 1939.

467. Report on Microchemical Methods. Alkoxyl Determination. E. P.
Clark. Jour. Assoc. Off. Agr. Chem., vol. 22, no. 3, pp. 622-624.
Aug. 1939.






-79 -

Index
No.
468. Wetting Power. A Study of Inorganic Salts as Adjuvants for In-
creasing Wetting Power. H. L. Cupples. Soap and Sanitary Chemicals,
vol. 15, no. 9, pp. 30-31, 41, September 1939,

469. Book Review on "World Economic Review of Insecticides and Allied
Products," June 1939 ed. 149 pages, mimeographed by L. W. Roskill &
Co., 46 Catherine Place, Buckingham Gate, London, S. W. 1. Price
5 pounds ($25.00). R. C. Roark. Indus. Engin. Chem., News Ed.,
vol. 17, no. 18, p. 614 (Sept. 20, 1939).

470. A Bibliography of Cyanide Compounds Used as Insecticides, 1933.
H. D. Young. Bureau of Entomology and Plant Quarantine Publ.
E-493. Mimeo. 40 pp. Sept. 1939.

471. A Field Method for the Chemical Evaluation of Spray Deposits Re-
sulting from the Application of Insecticides for Control of the
Codling Moth. J. E. Fahey and H. W. Rusk. Bureau of Entomology
and Plant Quarantine Publ. E-491. Multi. 9 pp., 4 figs. Sept.
1939.

472. Wetting and Spreading Properties of Aqueous Solutions. Mixtures of
Sodium Carbonate with n-Caproic, n-Caprylic, n-Capric, Lauric,
Myristic, and Palmitic Acids. H. L. Cupples. Indus. and Engin.
Chem., Indus. Ed., vol. 31, no. 10, pp. 1307-1308. Oct. 1939.

473. Chlorine Gas as a Seed Disinfectant. R. W. Leukel* and 0. A.
Nelson. Phytopathology, vol. 29, no. 10, pp. 913-914. Oct. 1939.

474. Effects of Heat Treatments of Some Calcium Arsenates on Their
Toxicity to Silkworms and Bean Plants. J. W. Bulger* and 0. A. Nel-
son. Jour. Econ. Ent., vol. 32, no. 5, pp. 615-619. October 1939.

475. Ease of Residue Removal from Late and Early Spray Applications of
Lead Arsenate to Apples. Jack E. Fahey, Harold W. Rusk, Loren F.
Steiner* and R. F. Sazama.* Jour. Econ. Ent., vol. 32, no. 5, pp.
714-717. Oct. 1939.

476. A Bibliography of Cyanide Compounds Used as Insecticides, 1934.
H. D. Young and R. L. Busbey. Bureau of Entomology and Plant
Quarantine Publ. E-494. Mimeo. 57 pp. October 1939.

477. Chemistry in Pest Control. R. C. Roark. Soap and Sanitary Chemi-
cals, vol. 15, no. 11, pp. 93, 95, 97, 123. Nov. 1939. (Also
published under the title "Importance of Chemistry in Pest Control,"
in Pests, vol. 7, no. 11, pp. 14-17, Nov. 1939.)

478. Allenes. I. The Preparation of l-Phenyl-l,2-Butadiene. Fred Acree.
Jr., and F. B. LaForge. Jour. Organic Chemistry, vol. 4, no. 5,
pp. 569-574. Nov. 1939.







80 -

index
NO.
47z. A M3thod for Datermining D3guelin in Darris and Cube. L. D. Goodhue
and H. L. Haller. Indus. Engin. Chem., Anal. Ed., vol. 11, no. 12,
pp. 64)-642. December 15, 1939.

430. Analysis of the Water Extract of Derris and Cube. L. D. Goodhue
and H. L. Haller. Jour. Econ. Entom., vol. 32, no. 6, pp. 877-879.
Dec. 1939.




-81 -


PATENTS OF THE DIVISION OF INSECTICIDE INVESTIGATIONS,


Index
No.
1. 1,789,322 (Jan. 20, 1931; apple. Nov. 23, 1927). MATERIAL FOR KILLING
INSECTS. R. C. Roark and R. T. Cotton.* (Chloroacetates
as fumigants.)

2. 1,791,429 (Feb. 3, 1931; apple. Feb. 23, 1929). INSECTICIDE AND FUMI-
GANT. R. C. Roark and R. T. Cotton.* (Ethylene oxide as
an insecticidal fumigant.)

3. 1,842,443 (Jan. 26, 1932; apple. Nov. 15, 1929). PROCESS FOR THE
MANUFACTURE OF INSECTICIDES AND METHOD OF MAKING SAME.
R. H. Carter. (Manufacture of double fluorides of the alkali
metals with aluminum by treatment of a water insoluble com-
pound of aluminum with alkali metal compounds and hydro-
fluoric acid.)

4. 1,863,266 (June 14, 1932; appl. Nov. 15, 1929). PROCESS FOR THE
MANUFACTURE OF INSECTICIDES AND METHOD OF MAKING SAME.
R. H. Carter. (Manufacture of double fluorides of the
alkali metals with aluminum in admixture with hydrated
silica as diluent by treatment of water soluble salts of
aluminum with alkali metal compounds and hydrofluosilicic
acid.)

5. 1,863,519 (June 14, 1932; appl. Nov.15, 1929). PROCESS FOR THE MANUFAC-
TURE OF INSECTICIDES AND METHOD OF MAKING SAME. R. H.
Carter. (Double fluorides of the alkali metals with aluminum
in admixture with hydrated alumina as diluent by treatment
of water soluble salts of aluminum with alkali metal com-
pounds and hydrofluoric acid.)

6. 1,884,966 (Oct. 25, 1932; appl. Feb. 19, 1930). PROCESS FOR THE
REMOVAL OF NATURAL OILS, WAX, AND SPRAY RESIDUES FROM
FRUITS. R. H. Robinson. (With hydrochloric acid, water, and
a petroleum hydrocarbon.)

7. 1,885,100 (Oct. 25, 1932; appl. July 11, 1929). PROCESS FOR THE
REMOVAL OF SPRAY RESIDUES FROM FRUITS AND VEGETABLES. R. H.
Robinson. (By means of a mixture of hydrochloric acid and
ferrous sulphate.)

8. 1,928,256 (Sept. 26, 1933; appl. Aug. 23, 1930). INSECTICIDE AND
PROCESS OF MAKING THE SAME. H. A. Jones. (Colloidal dis-
persions of rotenone by the aid of pyridine.)

i Copies of all patents can be obtained for 10 cents (no postage) sent to
the Patent Office, Washington, D. C. In ordering a copy of a patent the
number of the patent, the date, the name of the patentee, and the subject
of the invention should be stated.





-82 -
Index
No.
9. 1,923,963 (Oct. 3, 1933; apple. Aug. 23, 1930). PROCESS FOR MAKING
AN INS=TICIDE. H. A. Jones. (Colloidal dispersions of
rotenone by the aid of tannic acid.)

10. 1,933,975 (Nov. 7, 1933; apple. May 29, 1933.) PROCESS OF PREPARING
ACYLATED PHENOLS. H. L. J. Haller and P. S. Schaffer.

11. 1,942,104 (Jan. 2, 1934; apple. Feb. 20, 1933). PROCESS OF EXTRACTING
ROTENONE FROM PLANT MATERIAL. H. A. Jones. (By means of
carbon tetrachloride.)

12. 1,945,312 (Jan.30, 1934; apple. Apr. 10, 1933). PROCESS OF PREPARING
DIHIDhXROTEZJNE. H. L. J. Haller and P. S. Schaffer.

13. 2,024,027 (Dac. 10, 1935; apple. Apr. 10, 1931). FUMIGANT. R. T.
Cotton* and H. D. Young. (Ethylene oxide-carbon dioxide
mixture.)

14. 2,033,853 (March 10, 1936; apple. July 5, 1934). COM?OUNDS OF BENTONITE
WITH ORGANIC BASES AND PROCESS OF PRODUCING SAME. C. R.
Smith.

15. 2,044,5D2 (June 16, 1936; appl. Feb. 18, 1936). PROCESS FOR THE
PURIFICATION OF PYRETHRIN CONCENTRATES. H. L. J. Haller
and F. B. LaForge.

16. 2,046,546 (July 7, 1936; apple. May 23, 1934). PROCESS FOR THE REMOVAL
OF INSECTICIDAL RESIDUES FROM FRUITS AND VEGETABLES. R. H.
Carter. (Aluminum salts with and without dilute acids.)

17. 2,043,547 (July 7, 1936; appi. May 23, 1934). PROCESS FOR THE REMOVAL
OF INSECTICIDAL RESIDUES FROM FRUITS AND VEGETABLES. R. H.
Carter. (Ferric salts with and without dilute acids.)

18. 2,046,543 (July 7, 1936; apple. Miy 23, 1934). PROCESS FOR THE REMOVAL
OF INSECTICIDAL RESIDUES FROM FRUITS AND VEGETABLES. R. H.
Carter and J. E. Fahey. (Boric acid with dilute mineral
acids.)

19. 2,049,725 (Aug. 4, 1936; apple. March 20, 1935). INSECTICIDE. L. E.
Smith. (Diaryl thioxins, especially phenothioxin.)

23. 2,050.974 (Aug. 11, 1936; apple. Sept. 12, 1935). PROCESS OF PREPARING
A PJRIFIED PYR3TARIN CONCENTRATE. F. B. LaForge and H. L. J.
Haller.

21. 2,03,539 (Nov. 10, 1936; apple. May 21, 1935). PROCESS FOR OBTAINING
FREE SILVER AND IODINE FROM SILVER IODIDE. J. R. Spies.

22. 2,063,941 (Jan. 5, 1937; apple. July 9, 1935). INSECTICIDE AND PROCESS
FOR MAKING THE SAME. L. N. Markwood. (Nicotine humate.)







83 -

Index
No.
23. 2,03),034 (May 11, 1937; apple. Miy 17, 1933). DDJ3LE SALT OF COPPER
A3.3NITE AN) A COOPER SALT OF AN UJ3ATJ3ATSD FATTY ACID
AND PROCESS OF MAKING THE SAME. F. E. D3arborn.

24. 2,094,831 (Oct. 5, 1937; apple. June 27, 1936). INSECTICIDE. D. L.
Vivian and H. L. Haller. [Covers tha use as insecticides of'
hydroxy azo compounds containing at least one hydroxy group
and at least one nitro group; for example, 4-(p-nitro-
phenylazo)-resorcinol and l-(p-nitrophenylazo)-2-naphthol.I

25. 2,095,738 (Oct. 12, 1937; apple. Jan. 29, 1937). THERMOREGJLATOR.
L. D. Goodhue.

26. 2,095,939 (Oct. 12, 1937; apple. June 27, 1936). INSECTICIDE. D. L.
Vivian and H. L. Haller. [This insecticide comprises an
aryl hydroxy azo compound in which the nuclei are substituted
by one azo, one or more hydroxy, and one or more halogen
groups; for example, p-(p-bromophenylazo)-phenol 4-(p-
bromophenylazo)-resorcinol, and 4-(2,5-dichlorophenylazo)-
phenol.]

27. 2,095,940 (Oct. 12, 1937; apple. June 27, 1936). INSECTICIDE. D. L.
Vivian and H. L. Haller. [This insecticide comprises an
arylazo compound in which the nuclei are substituted by ai
least one halogen atom; for example, p-iodoazobenzene.]

28. 2,095,941 (Oct. 12, 1937; apple. June 27, 1936). INSECTICIDE. D. L.
Vivian and H. L. Haller. [This insecticide comprises a com-
pound containing homocyclic nuclei joined by one azo group,
and containing in addition to not less than one hydroxyl
group, not less than one halogen atom and not less than
one alkyl group; for example, 4-(2,5-dichlorophenylazo)-o-
cresol, 4-(p-bromophenylazo)-o-cresol, and 4-(p-bromophenyl-
azo)-m-cresol.]

29. 2,096,414 (Oct. 19, 1937; appl. June 27, 1936). INSECTICIDE. D. L.
Vivian and H. L. Haller. [This insecticide comprises a com-
pouai saleoted from the group consisting of 4-phonylazo-o-
toluiding, 4-2henylazo-m-toluidine, p-(o-tolylazo)-aniline,
p-(m-tolylazo)-aniline, p-(p-tolylazo)-aniline, l-(o-toly-
lazo)-2-naphthylamine, 4-(o-tolylazo)l-naphthylamine, 1-
(m-tolylazo)-2-naphthylamine, 1-(p-tolylazo)-2-naphthylamine.
4-(m-tolylazo)-l-naphthylamine, 4-(p-tolylazo)-l-naphthyl-
amine, and 4-(o-tolylazo)-o-toluidine.]

30. 2,096,566 (Oct. 19, 1937; apple. Dec. 27, 1933). COMPOUND AND PROCESS
FOR MAKING SAME. C. R. Smith. [An insecticide comprising
nicotine-bentonite compounds.]






- 84 -


Index
No.
31. 2,096,715 (Oct. 26, 1937; apple. Feb. 26, 1937). PROCESS OF PREPARING
DIHYDROJASMONE. H. L. Haller and F. B. LaForge.

32. 2,099,826 (Nov. 23, 1937; apple. July 22, 1937). INSECTICIDE. P. S.
Schaffer and H. L. Haller. [Dialkylacridan.]

33. 2,100,493 (Nov. 30, 1937; apple. June 3, 1936). INSECTICIDE. L. E.
Smith and H. V. Claborn. [o-, m-, and p-Nitroiodobenzenes.]

34. 2,103,195 (Dec. 21, 1937; appl. July 3, 1937). INSECTICIDE. H. A.
Jones. [Combination of rotenone and dichloroacetic acid.]

35. 2,104,584 (Jan. 4, 1938; appl. Oct. 15, 1934). DOUBLE SALTS OF COPPER
ARSENITE AND A COPPER SALT OF A HIGHER UNSATURATED FATTY
ACID. F. E. Dearborn. [Compounds containing arsenic,
copper and the anyhdride of a fatty acid of the general
formulae CnH2n-402 and CnH2n-60.]

36. 2,107,058 (Feb. 1, 1938; refiled for abandoned apple. Serial No.
744,636, Sept. 19, 1934. This application June 24, 1937,
Serial No. 150,165). PROCESS FOR MAKING AN INSECTICIDE.
L. N. Markwood. [Nicotine peat.]


37. 2,110,614 (March 8, 1938; apple. May 10, 1937).
Vivian and H. L. Haller. [Phenazine.]


INSECTICIDE.


38. 2,110,896 (March 15, 1938; apple. June 27, 1936). INSECTICIDE. D. L.
Vivian and H. L. Halle. [This insecticide comprises a
compound of the general formula CH3 R, N = N R, OH
where R, and R2 denote interchangeable homocyclic aryl
nuclei, R, being a single benzene ring and R2 a naphthyl
nucleus, for example, 1-(o-tolylazo)-2-naphthol and 4-
(o-tolylazo)-l-naphthol,]


39. 2,110,897







40. 2,111,879


(March 15, 1938; appl. June 27, 1936). INSECTICIDE. D. L.
Vivian and H. L. Haller. [This insecticide comprises a
compound of the general formula R N : N R, (OH) where
R and R, denote interchangeable homocyclic aryl nuclei,
R being a single benzene ring and R, a naphthyl nucleu.,
for exam-mle, 4-phenylazo-l-naphthol, (1-naphthylazo)- phenol,
and 4-(2-naphthylazo)-l-naphthol.]

(March 22, 1938; apple. June 27, 1936). INSECTICIDE. D. L.
Vivian and H. L. Haller. [This insecticide comprises a
compound of the general formula R, N = N R2 (NH2)
where R, and R3 denote interchangeable aryl nuclei, R1
being a single benzene nucleus and R2 a naphthyl nucleus,
for example, 1-phanylazo-2-naphthylamine, p-(l-naphthylazo)-
aniline, and 1-(l-naphthylazo)-2-naphthylamine.]


D. L.





85 -

Index
No.

41. 2,114,092 (Apr. 12, 1938; apple. Mar. 9, 1937). MECHANICAL DUSTER.
L. D. Goodhue.

42. 2,115,046 (Apr. 26, 1938; apple. Feb. 26, 1937). INSECTICIDE. L. E.
Smith. [4,6-Dinitro-o-tolyl methyl ether.]

43. 2,123,248 (July 12, 1938; apple. Jan. 14, 1937). INSOLUBLE REACTION
PRODUCTS OF PEAT AND PROCESS OF MAKING SAME. L. N. Mark-
wood. [Water-insoluble reaction products of peat with
organic bases of the group consisting of arecoline, anabasine,
codeine, ethylene diamine and piperidine.]

44. 2,127,090 (Aug. 16, 1938; apple. Feb. 26, 1937). INSECTICIDE. L. E.
Smith. [4,6-Dinitro-o-tolyl acetate]

45. 2,127,380 (Aug. 16, 1938; appl. Apr. 14, 1937). INSECTICIDE AND
FUNGICIDE. Frederick E. Dearborn. [Compounds of copper,
arsenic, and unsaturated acids]

46. 2,129,517 (Sept. 6, 1938; apple. Jan. 10, 1938). ADHESIVE FOR INSECTI-
CIDES AND A PROCESS FOR MAKING SAME. Lyle D. Goodhue.
(Pine-oil foots)

47. 2,135,551 (Nov. 8, 1938; apple. Sept. 24, 1936). FUNNEL HEATING
DEVICE. Louis N. Markwood.

48. 2,140,481 (December 13, 1938; appl. Jan. 28, 1938). INSECTICIDE.
William G. Rose and Herbert L. J. Haller. [Pentaerythrityl
bromide.]

49. 2,146,257 (Feb. 7, 1939; appl. Sept. 23, 1938). ADHESIVE FOR INSECTI-
CIDES. L. D. Goodhue. [Furfural with amines.]

50. 2,146,258 (Feb. 7, 1939; appl. Sept. 26, 1938). ADHESIVE FOR INSECTI-
CIDES. L. D. Goodhue. [Furfural with ketones.]

51. 2,149,303 (March 7, 1939; appl. Oct. 13, 1938). LIQUID MEASURING
DEVICE. L. N. Markwood.

52. 2,150,759 (March 14, 1939; appl. Jan. 28, 1938). INSECTICIDAL AND
FUNGICIDAL COMPOSITIONS. R. H. Carter. [Cuprous amyl
xanthate and diamyl xanthogen composition.]

53. 2,155,010 (April 18, 1939; apple. April 1, 1938). INSECTICIDE. Andrew
F. Freeman. [N-nitrosodiphenylamine.]

54. 2,159,585 (May 23, 1939; apple. Jan. 28, 1938). COMPOUNDS OF COPPER,
ARSENIC, AND A SULPHMONOCARBOXYLIC ACID AND PROCESSES OF
MAKING THEM. F. E. Dearborn.







- 86 -


Index
No.
55. 2,163,000 (June 20, 1939; apple. June 14, 1938).
PARATUS. L. D. Goodhue and C. M. Smith.


SEDIMENTATION AP-


56. 2,169,793 (Aug. 15, 1939; apple. Feb. 11, 1937). PROCESSES OF TREATING
GLYCERIDES. F. E. Dearborn.


57. 2,173,333 (Sept. 19, 1939; apple. Aug. 16, 1937).
R. H. Carter. [Ethylene glycol]

58. 2,173,384 (Sept. 19, 1939; apple. Aug. 16, 1937).
R. H. Carter. [Diethylene glycol]


COPPER XANTHATE.


COPPER XANTHATE.


59. 2,173,386 (Sept. 19, 1939; apple. Feb. 6, 1939). INSECTICIDE. D. L.
Vivian. [Hydrazobenzene]

60. 2,175,109 (Oct. 3, 1939; apple. July 22, 1937). INSECTICIDE. H. V.
Claborn and L. E. Smith. [9-Chlorofluorene.]





-87 -

AUTHOR I

(The asterisk indicates that the author is not a member of the
Division of Insecticide Investigationks. The letter "P" refers to thco list
of patents which follows the list of publications. Numbers used here are
the index numbers of the publications and patents listed.)

Anon ........................ 269
*Abbott, W. S ... ............. 66
Acree, F., Jr..................... 220, 263, 297, 302, 370, 478, 481
*Back, E. A ... ................. 64, 85
Barnes, J. W... 26, 40, 48, 49
*Beaumont, J. H ................... 242, 252, 398
*Bishopp, F. C ..................... 1, 20, 123
*Bulger, J. W .................... 474
Busbey, R. L ................ 148, 247, 250, 253,'277, 306, 319, 350, 400, 431,
432, 449, 476
*Cambell, F. L ................... 177, 178, 210, 215, 233, 245, 284
Capen, R. G ....................... .403
Carter, R. H ....................... 21, 22, 38, 55, 67, 68, 97, 100, 102, 146, 156,
157, 158, 186, 194, 195, 201, 212, 225, 226, 267,
311, 354, 403, 432, 433, 463
P 3, P 4, P 5, P 16, P 17, P 18, P 52, P 57, P 58
Cassidy, John ...................... 278, 465
Cassil, C. C ... ......... 252, 305, 325, 338, 344, 359, 386, 390. 391, 398,
403, 444, 446.
Chisholm, R. D ................... 420, 442, 450
Claborn, H. V ..................... 155, 272, 339, 381, 388
P 33, P 60
Clark, E. P ......................... 41, 56, 60, 87, 89, 92, 104, 108, 111, 118, 131,
136, 144, 151, 155, 163, 171, 175, 182, 197, 198,
203, 214, 227, 255, 262, 290, 310, 316, 333, 362,
365, 389, 416, 417, 418, 422, 456, 467
*Clifford, P. A ... ......... 2C8
*Cotton, R. T ....................... 2, 6, 8, 11, 16, 30, 54, 64, 85, 273, 294. 309,
336, 346, 358, 361, 428
P 1, P 2 P 13
*Cox J H ........................... 64
*Cressman, A. W.............. 224, 299, 330
Cupples, H. L ..................... 166, 167, 172, 259, 266, 275. 281, 283, 284, 288,
298, 349, 379, 383, 468, 472
*Davidson, J ......................... 391
*Davidson, W. M ................... 43, 66, 95, 96
*Davis, A. C ...................... 216, 237, 246, 272
Dawsey, L. H ....................... 161, 188, 224, 292, 299, 330, 371
D3arborn, F. E .......... 63, 71, 260, 235, 324, 337, 357, 369, 411
P 23, P 35, P 45, P 54, P 56
*Diehl, H. C ......................... 72, 81, 142
Drake, N. L........................ 75, 130, 148, 149, 192, 236, 243, 400
Fahey, J. E........................ 59, 72, 81, 142, 153, 183, 212, 256, 301, 348,
384, 402, 405, 407, 439, 447, 451, 471, 475
P 18





- 88 -


*Fink, D. E .............. 296, 303, 304, 331, 381
Freeman, A. F ..................... 408
P 53
Gersdorff, W. A..-........ .43, 70, 79, 86, 103, 132, 174, 177, 189, 213,
257, 253, 270, 323, 335, 388, 415, 460
Gertler, S. I .... ............ 425
Gooden, E. L ........ .............. 177, 274, 332, 368, 440
Goodhue, L. D ....... ..... 276, 308, 315, 343, 367, 368, 374, 386, 396, 420,
436, 437, 440, 457, 479, 430
P 25, P 41, P 46, P 49, P 50, P 55
*Gould, Edwin .. ...... ...... -325, 398
*Graham, J. J. T ................ 373, 377
Gross, C. R ............... ..... 59, 168, 196, 205, 212, 219, 242, 251
Haag, H. B ........ ....... 119, 180
*Haas, A J ..................... 161
Haller, H. L .. ...... 61, 69, 82, 93, 109, 110, 117, 124, 126, 129,
137, 138, 139, 160, 179, 181, 190, 193, 199, 204,
207, 220, 223, 228, 231, 233, 263, 265, 280, 282,
291, 296, 297, 307, 318, 326, 328, 329, 331, 339,
340, 341, 353, 355, 382, 385, 397, 399, 401, 406,
408, 413, 424, 425, 430, 436, 443, 453, 457,
453, 479, 480
P 10, P 12, P 15, P 20, P 24, P 26, P 27, P 28,
P 29, P 31, P 32, P 37. P 38, P 39. P 40, P 48
*Haller, M. H .................. 242, 252, 325, 398
*Haring, M. M ....................... 363
*Harris, M ..... .................. 208
Hiley, J ............................. 284, 298, 330, 371
*Hillig, F ............................. 416 417
Jones, H. A ......................... 62, 95, 96, 101, 110, 113, 122, 133, 164, 165,
169, 176, 177, 202, 210, 215, 217, 245, 264, 289,
322, 334, 352, 366, 373, 377, 380, 395, 423, 441,
459, 464
P 8, P 9, P 11, P 34
*Keenan, G. L ................... .66, 94, 125, 163, 228
Koblitsky, L ...................... 462
*Laake, E. W ................ 1, 20, 123
LaForge, F. B .... 17, 18, 19, 31, 35, 51, 52, 53, 61, 65, 69, 74,
82, 83, 109, 115, 117, 120, 124, 125, 126, 129,
137, 150, 152, 179, 191, 223, 231, 232, 265, 282.
291, 302, 307, 328, 329. 340. 341. 355, 370, 393,
399, 430, 443, 478, 481
P 15, P 20, P 31
*Lathrop, F. H ............. 284
*Leukel, R. W... .... ....... 364, 473
*Loughrey, J. H ............... 208
Love S ............ ........ 366
Markwood, L. N .............2...2 6, 287, 351, 378, 393. 410, 445. 455
P 22, P 36. P 43, P 47, P 51
*McDonnell, C. C C6
*McGovran, E. R............4C6




-89 -


*MoIndoo, N. E ..................... 306, 319
*Munger, F ............................. 261, 295, 312. 387, 435, 461
Murray, C. W ...................... 40, 48, 91, 141, 154, 208, 212, 252, 278, 398,
454, 466
Nelson, 0. A ............. 14, 23, 24, 27, 29, 66, 73, 84, 128, 135, 185,
205, 229, 230, 314, 344, 353, 360, 363, 364, 452,
473, 474
*Newcomer, E. J ................... 100, 186, 194, 201
*Palkin, S ............................. 230
*Parman, D. C ..................... 1, 20, 123
*Phillips, G. L ............... 406
*Pulley, G. N ....................... 391
*Reeves, E. L ................... 466
*Richardson, C. H ............ 80
*Richardson, H. H ............... 350
Roark, R. C ......................... 1, 2, 3, 5, 6, 7, 8, 9, 10, 11, 12, 15. 16, 20,
21, 25, 28, 29, 32, 34, 36, 42, 44, 46, 50, 54,57,
58, 76, 77, 78, 84, 85, 90, 94, 98, 99, 105, 106,
107, 112, 114, 116, 123, 134, 140, 143, 145, 147,
159, 170, 184, 187, 200, 206, 209, 211, 218, 221,
238, 239, 240, 244, 248, 250, 253, 254, 271, 277,
279, 293, 300, 319, 327, 345, 372. 375, 394. 404,
409, 414, 419, 421, 426, 427, 429, 434, 438, 448,
469, 477
P 1, P 2
Robinson, R. H ................ 39
P 6, P 7
Rose, W. G ........................... 318, 382
P 48
Rusk, H. W ........................... 242, 301, 313, 347, 348, 384, 402, 407, 439, 471,
475
*Ryall, A. L ..................... 72, 153, 212, 278, 454
*Sazama, R. F ....................... 256, 301, 384, 402, 405, 407, 475
Schaffer, P. S .................. 193, 199, 204, 297, 331, 458
P 10, P 12, P'32
Schechter, M. S ................. 397, 401, 413, 453
*Shepard, H. H ..................... 80, 195
*Siegler, E. H ..................... 261. 295, 312, 367, 387, 435, 437, 461
Smith, C. M ......................... 62, 91, 169, 219, 268, 274, 289, 305, 315, 332,
359
P 55
Smith, C. R ......................... 13, 33, 47, 80, 88, 121, 127, 178, 222, 249.
356
P 14, P 30
*Smith, E ............................... 212, 278, 465
Smith, L. E ......................... 35, 51, 52, 65, 74, 83, 115, 124, 139, 150, 179.
181, 207, 232, 233, 261, 295, 304, 312, 321, 376,
381, 387, 392, 412, 424, 435, 461
P 19, P 33, P 42, P 44, P 60
Spies, J. R ......................... 75, 130, 149, 162, 173, 192, 234, 235, 236, 241,
243, 317, 320, 342
P 21







- 90 -


*Steiner, L. F ................... 256, 301, 384, 402, 405, 407, 447, 451, 475
*Sullivan, W. N ................... 177, 178, 210, 215, 233, 245, 264, 352, 385, 395,
406, 457
*Summerland, S. A ............... 447
*Swenson, R. L .................... 4
Vivian, D. L ....................... 303, 381
P 24, P 26, P 27, P 28, P 29, P 37, P 38, P 39,
P 40, P 59
*Vorhes, F. A., Jr ............. 208
*Wagner, G. B ....................... 273, 294, 309, 336, 346, 358, 361, 428
*Weigel, C. A ....................... 4
*Wichmann, H. J ................... 208, 446
*Yothers, M. A .. ..... ........ 466
Young, H. D ......................... 4, 27, 30, 37, 45, 64, 128. 185, 216, 237, 246,
247, 273, 294, 309, 336, 346, 358, 361, 428, 470
476
P 13
*Yust, H. R ........................... 284, 298





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