Title: Florida Entomologist
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Title: Florida Entomologist
Physical Description: Serial
Creator: Florida Entomological Society
Publisher: Florida Entomological Society
Place of Publication: Winter Haven, Fla.
Publication Date: 1937
Copyright Date: 1917
 Subjects
Subject: Florida Entomological Society
Entomology -- Periodicals
Insects -- Florida
Insects -- Florida -- Periodicals
Insects -- Periodicals
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General Note: Eigenfactor: Florida Entomologist: http://www.bioone.org/doi/full/10.1653/024.092.0401
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Volume ID: VID00278
Source Institution: University of Florida
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Florida Entomologist
Official Organ of the Florida Entomological Society
VOL. XX NOVEMBER, 1937 No. 3

TOMATO PIN WORM (Gnorimoschema lycopersicella (Busck))
IN FLORIDA
By GEORGE R. SWANK
The following account of the tomato pin worm (Gnorimos-
chema lycopersicella) is a condensation of a report submitted
to the State Plant Board at Gainesville, descriptions of the
stages with the details of their activities as well as the tables
and drawings being omitted.
The investigation was carried on from April 1 to June 30,
1937. The State Experiment Station insectary was used and
the work was done under the direction of Professor J. R.
Watson.
The living larvae with which the investigation was started
were procured from materials sent in to the State Plant Board
taxonomist, Mr. G. B. Merrill, by inspectors working in Osceola,
Polk, Orange and Seminole counties, and from materials brought
by Professor Watson from Manatee County.
The first adult moths emerged from the collected material
on April 22. They were found to be five females and two males.
By the next day eleven more adults had emerged.
Seven adults, four females and three males, were placed
in a lamp chimney and supplied with a fresh tomato leaf on
May 23. Eggs were found on the leaf the next day and these
hatched on May 31.
In order to determine the time spent in each instar, without
the danger of injuring the tiny larvae in removing them from
the leaves, the following technique was followed. Seven adults
were confined in a lamp chimney with a fresh tomato leaf for
twenty-four hours. The leaf was kept fresh as long as possible
by having the petiole pass through a cork into a small bottle
of water. Fresh leaves were supplied in each lamp chimney
as they wilted or were consumed by the growing larvae. Each
day the moths were removed to a different lamp chimney.









THE FLORIDA ENTOMOLOGIST


When a moth was found dead it was replaced by another moth
of the same sex and thus the number was maintained at seven.
When the moths were removed the leaf and container were
examined and the eggs counted. Occasionally eggs laid the same
night had to be supplied from other sources in order to have
at least twenty eggs in each lamp chimney.
On May 14 and again on May 21 five larvae were removed
from each lamp chimney and placed in separate vials of alcohol.
The width of the head capsule of each larva was later taken
and by the aid of Dyer's law the following table of larval in-
stars was derived.
First instar-up to 4 days. Avg. 2.33 days
Second instar-from 3rd to 9th day. Avg. 2.65 days
Third instar-from 6th to 10th day. Avg. 3.33 days
Fourth instar-from 9th to 17th day. Avg. 2.04 days
Average number of days in larval stage-10.35 days.
The full grown larva may spend from part of one day up
to two days after it has ceased to feed until it changes to a
pupa. Only about ten minutes pass from the time the head
capsule splits on the back until the last larval skin has been
worked to the posterior end of the abdomen.
During the middle of April pupae from larvae which were
brought into the insectary lasted from nine to sixteen days
with an average of 10.5 days for the 30 cases for which accurate
time records were kept. The temperature over this period
(April 10-25) averaged* 69.6 degrees F.
The temperature averaged 79.8 degrees F. during the time
the next generation was in the pupal stage, from May 20 to
June 3. The males spent from 8 to 11 days with an average
of 9.11 days while the females averaged only 8.24 days with
a spread of from 7 to 10 days. The average for both sexes
was 8.64 days as compared with 10.5 days which the previous
generation spent in the pupal state.
The adult moths of the third generation were just starting
to emerge at the close of the investigation. The indications
were that the pupal period would average somewhat shorter
but not enough cases could be checked to get accurate results.
Both males and females were found mating the evening of
the same day on which they emerged. Copulation takes place

*The average of the maximum and minimum for each day as recorded
by the nearby U. S. Weather Bureau thermometers.









VOL. XX-No. 3


during the late evening or early morning and lasts from 10
minutes to an hour and a quarter.
Eggs were deposited by mated females on the first night
after they had emerged. Eggs may be laid at any time of the
day or night but most of them are laid during the morning
or evening twilight at which time the moths are normally more
active. It takes only about five seconds to deposit an egg and
several may be laid in a few minutes. Eggs may be deposited
at any time during the life of the adult female moth which
may cover a period of almost a month.
There are indications of considerable seasonal variation in
the time it takes to complete a life cycle. Since this work was
done in the early summer only, there was not opportunity to
check these seasonal variations. It is interesting, however, to
compare the results which were obtained in Florida with those
published by Campbell' and Elmore for California.
Florida (California)
Minimum Maximum Average
Incubation .................. 4 (4) 9 (30) 6.7 (8.9)
Larval period ............ 9 (9) 17 (63) 9.8 (27.9)
Pupal period .-- -- 7 (15) 17 (52) 11.0 (30.2)
Egg to adult ............ 20 (28) 43 (145) 27.5 (67.0)
It will be noticed that the development in Florida for the
time of the year covered by this work corresponds rather closely
with the minimum for California. This might be expected since
the tomato pin worm is probably native to the warmer climates
and Gainesville is several degrees closer to the equator than
California. During the latter part of June an entire life cycle
was completed in 21 days.
Instances were noted in which the male moths mated more
than once. In no case was more than one copulation noted for
any female.
Without food the female can be expected to live from six
to twenty-five days after copulation while the male will prob-
ably die before the sixth day, and frequently do so within forty-
eight hours.
If proper food is obtained it is possible that they would live
considerably longer. On the second of June 16 virgin females
were placed in a large test tube and fed with honey and water
daily. Nineteen males which had not mated were treated simi-
1CAMPBELL, ROY E. and ELMORE, J. C. The Tomato Pinworm. Bulletin
of Dept. of Agri., Vol. XXIV, No. 3, July-Sept., Sacramento, Calif., pp.
301-309.







THE FLORIDA ENTOMOLOGIST


larly and by June 23 only four males and one female had died.
On June 30, at the end of 28 days, seven males and ten females
were still alive.
We see, therefore, that feeding increases the length of life
possible for unmated moths and would probably increase the
length of life after mating also as well as the number of eggs
laid. Accurate data were not gathered on this point. The fact
that the largest number of eggs deposited over the longest
period by a single individual were laid by a female which was
being fed honey and water would, however, probably lend weight
to this idea.
The largest number of eggs from one female was 138, de-
posited on 15 of the 18 days she lived after mating. Forty-three
eggs was the largest number laid by one female in a 24-hour
period. The average number of eggs laid by 24 mated females
was 36.1. Two of these died before any eggs were deposited.
Very few eggs were laid by unmated females and none of
these hatched. Only one egg was found in groups known to be
from fertilized females in which the embryo was not developing
and it is possible that this egg had been injured.
The adult moth is a fairly strong flyer although its flights
are somewhat shaky or in the form of a spiral during the day.
At night their flights are probably longer and this is very likely
the way that they spread within a given infested area. It is
possible that their natural flights might account for their estab-
lishment in another trucking section if it were not too far dis-
tant. In Florida, however, where one trucking section may be
separated from the next by miles of uncultivated land, this
means of dispersal seems improbable except with the aid of
air currents.
Further investigation might reveal some native Florida
plants on which the larvae could live and develop properly and
which would serve to bridge the extensive uncultivated lands.
So far no such plant has been found. The nearest approach to
it is found in the cherry-tomato which sometimes grows as an
escape in waste lands or hammocks. Solanum sisymbriifolium
Lam. may also occasionally be found growing in Florida as a
weed.
A common means of distribution is quite likely on tomatoes
or packing material. A bushel of infested tomatoes was brought
from the southern part of the state for use in making a check
of insect parasitism on the tomato pin worm. They were trans-








VOL. XX-No. 3


ported in a burlap sugar sack. Moths emerged from the empty
sack from three to ten days after it arrived. Thus it can be
seen that containers in which tomatoes are shipped may become
a source of infestation for some time even after the tomatoes
have been consumed. It is probable that this time would be
considerably increased if the pupae were subjected to lower
temperatures either through refrigeration or in being shipped
to a colder climate.
Ordinarily by the time the tomatoes are ripe enough for
the retail market few pin worms still remain in them. Most
of them leave the tomato to pupate and often those which do
remain are not able to find their way out when they become
adult moths. This may be due to the change in the position of
the tomato in shipment, to the fact that the hole through which
the moth would have escaped has become closed by fungus
growth or juice from the broken tissue.
Another possible source of spread of this insect which needs
to be investigated and means provided for any control that may
be necessary is the shipment of large numbers of tomato plants.
It is probable that the transportation of young plants is the
most important means of dispersal over the state.
Several attempts were made during the process of this in-
vestigation to induce the moths to deposit eggs on various plants
or plant parts, other than tomato, with but indifferent success.
In addition to this difficulty the fact that larvae will immediately
crawl from the plant when they have hatched if the material is
not exactly to their taste led to confining the various sized larvae
with the material to be tested.
On April 8 when the living material was received from the
southern part of the state, 5 larvae of various sizes were placed
with several of the common weeds as a preliminary test of their
ability to survive. Natal grass (Tricholaena rose Ness.), green
briar (Smilax auriculata Walt.), pokeweed (Phytolacca rigida
Small.), cudweed (Gnaphalium spalutalum Lam.), Spanish
needles (Bidens pilosa Linn.), and horseweed (Leptilon cana-
dense Linn.), produced only negative results. The larvae all
died within a few days with no increase in size nor feeding
being evident.
The results were positive or doubtful in the following cases:
nightshade (Solanum gracile Link.), Florida tomato (S. aculea-
tissimum Jacq.), peppergrass (Lepidium virginicum Linn.),
potato and tomato foliage which was run as a check.








THE FLORIDA ENTOMOLOGIST


The reason for the results being doubtful in some of these
cases where only negative results appeared later was probably
due to the fact that not all of the larvae were tomato pin worm
larvae. Several potato tuber moths (Gnorimoschema operculella
Zell.)* and the nightshade moth (Gnorimoschema striatella)
were reared from this same material and it is easily possible
that there may have been others.
In the later tests, 10 larvae were placed separately on small
pieces of host material. These were then each caged in a 1.5
by 15 cm. test tube which was plugged with a cotton stopper.
Fresh host material was added daily. The old piece was re-
moved unless the larva was very small and had mined into
the leaf. Rather than risk the injury to the small larva in
removing it from the leaf-mine it was allowed to feed on the
old leaf until it left of its own accord.
In addition to the previous list cotton and corn were tried
as host materials from outside of the Solanaceae or nightshade
family. Peppergrass (Lepidium viginicum Linn.) was also re-
checked but in no case was feeding observed on any plant not
included in the Solanaceae.
Twenty-two tests were run on plants in the family Solana-
ceae. The tomato pin worm fed on only nine of these readily
enough to carry it through to pupation. They were the garden
tomato (Lycopersicum esculentum Linn.), cherry tomato (L.
cerasiforme Dunal.), potato (Solanum tuberosum Linn.), egg-
plant (S. melongena Linn.), S. sisymbrillfolium Lam., S. mexi-
canum, and two tests on S. citrullifolium A. Br.
One of the ten larva placed with the Fragrant Cultivated
Tobacco (Nicotiana sp.) reached the pupal stage. Since it
was a large larva it is possible that it pupated without having
eaten after it was placed on the leaf. Unfortunately there
was not sufficient time left to run another series.
A few of the larvae fed slightly on Solanum munistrum and
Datura stromonium Linn. As a result they lived longer than
those that did not feed but none which were placed on either
of these plants formed pupae.
The larva of the tomato pin worm starved when placed with
the following Solanaceous plants: Physaloides physaloides Linn.,
Physalis sp., Solanum glacile Link., S. capisicastrum Link., S.
nigrum Linn., S. munistrum, Capsicum annum Linn., Datura
*These determinations were made by H. H. Kiefer, Assistant Systematic
Entomologist of the State Department of Agriculture, Sacramento, Cali-
fornia.








VOL. XX-No. 3


metel Linn., D. stromonium Linn., Nicotiana tabacum Linn. and
Petunia hybrida Hort.
A series was also run on tomato petioles. Pieces of petiole
with no leaf were placed with the larvae. Most of them ate
more or less at the material even though they did not seem to
develop properly. In fact one larva lived three times as long
as it should have taken it to complete its larval growth but did
not grow nor pupate. The average length of time for the ten
larvae was almost twice as long as it should have taken to
reach the pupal stage, yet none of the ten pupated.
Attempts were made on various occasions to rear the insects
on green tomatoes. Fifty of the first larvae received were
placed on a green tomato and confined in a lamp chimney. Of
these only three emerged as adult moths. At another time
tomatoes were supplied in the lamp-chimney series instead of
the usual tomato leaf. Where the average number of adult
moths for the series was eleven, only one emerged from the
chimney containing the tomatoes. These figures are still more
significant when it is realized that five or ten larvae were re-
moved from most of the other lamp chimneys and placed in
alcohol for the purpose of measurement while none were re-
moved from the lamp chimney containing the tomatoes.
These instances would seem to give the impression that the
normal food of the tomato pin worm is the foliage rather than
the fruit, that infestation of the tomato is more of an incidental
matter. It is true that tomatoes may become highly infested
but since the attack is generally under the calyx lobes or at
a point where the tomato is in contact with a leaf or another
tomato, it would seem to be due to the reaction of the larvae
to select a small corner in which to start a mine rather than
a preference for the tomato. Observations in the field, how-
ever, seem to indicate that the larvae desert the leaves in favor
of the tomato when the fruit appears. This point needs fur-
ther checking under field conditions.
The only important hosts of the tomato pin worm in Florida
so far investigated are tomato, potato and eggplant. These
are all cultivated plants and as such can be watched by the.
grower better than weeds or wild plants.
The larvae are so small that the infestation may be much
higher than is realized by the casual observer. One hundred
twenty-four adult moths were reared on a potted tomato plant
which was only twelve inches high. Estimates were made that









THE FLORIDA ENTOMOLOGIST


the average larva consumed about three square centimeters of
tomato leaf during its larval development. The amount neces-
sary, however, may be considerably less than this. From these
figures it can be seen that the average tomato plant grown in
Florida could support several hundred larvae without stopping
the production of tomatoes.
Forty sound and 40 infested tomatoes were compared as
to their keeping qualities. The most of them were green when
the test was started and were matched for size and maturity.
They were placed on a table in the insectary and covered with
a cloth screen. Each day the tomatoes were examined and those
which were rotting were removed. When the test was closed,
at the end of 35 days, seven infested tomatoes had lain a total
of 939 days or an average of 23 and a half days each, as against
1168 days or an average of 29 days for the sound tomatoes.
The tomatoes had all ripened sufficiently to be used by the end
of ten days so that under ordinary conditions the difference
in keeping qualities would have made little difference between
the number of sound and infested tomatoes which reached the
retail market.
The presence of a larva or cavity in a tomato is often very
difficult to detect. This is especially true if the larva has entered
the tomato under the calyx and the calyx is still in place. The
hole where the larva entered is not only small and often well
hidden but may also be filled with a thin silken web which is
not easily seen even after the calyx has been removed. The
presence of a few tiny black pellets of frass which are held
in the delicate web may often be the only external evidence.
The larva may mine just under the surface of the tomato
where it produces a sunken darkened spot covered with a papery
tissue after the larva has left. It is more common, however,
for the mine to penetrate toward the center of the tomato. The
larvae seem to prefer the solid tissue but may occasionally be
found in the seed cavity of an unripe tomato.
The reasons why the grower will wish to avoid the tomato
pin worm besides the fact of the decrease of production due to
the reduced foliage are (1) the destruction of large numbers
of young plants in seedbeds, (2) increased cost due to the re-
quirement of closer inspection, (3) loss due to increased culling,
(4) the necessity of fumigating tomatoes to be shipped to
several states, (5) the danger of larval parts being found in
the processed product with resulting decrease in quality and









VOL. XX-No. 3


sale value, and (6) the poorer quality of the finished product.
In regard to this last point, many tomatoes which are attacked
when small become somewhat leathery and remain green in
the center when mature. In addition, many tomatoes will be
found with the interior of the seed cavity turned black as a
result of the entrance of fungi when the larval tunnel was
open. These blackened spots require considerable trimming
or a resulting inferior product.
Ten parasites emerged from the first material brought into
the laboratory. These with six others which emerged from
material brought later were sent to the National Museum of
Washington, D. C., for determination. Almost one hundred
other parasites emerged later but no opportunity was left for
study and comparison after the above determinations were re-
turned.
The second supply of material which was brought from
Sarasota County about May 30th seemed to be much more highly
parasitized than that which had been collected there about six
weeks previous. In fact it seemed to be difficult to find larvae
in the foliage. However, a quart of foliage which was col-
lected yielded more parasites than half a bushel of infested
tomatoes. It is possible that the larvae which were in the
tomatoes were better protected from the parasites than those
in the leaves.
Pupae and cocoons were buried at various depths in moist
and dry sifted sand. The greatest depth from which moths
emerged was one-half an inch. One adult out of five succeeded
in reaching the surface through this depth of moist sand and
two of ten in dry sand. By the time they had reached the
surface, however, they appeared light in color due to the loss
of scales from their wings and were scarcely able to fly.

SUMMARY
1. The tomato pin worm completed a life cycle in as short
a time as 21 days in Florida during the month of June.
2. The egg laying period of the female continues until near
enough to the emergence of the next generation so that a con-
tinuous infestation may be expected.
3. Under favorable conditions parasites become very num-
erous and their effect as a check on the number of tomato pin
worms is important.









THE FLORIDA ENTOMOLOGIST


4. The shipment of plants, tomatoes and shipping containers
are the most potent means of spreading the insect from one
trucking district to another.
5. The feeding of the larvae is confined to tomato, potato,
eggplant and a few other plants included in the Solanaceae
family. They are unable to complete the life cycle when placed
on wild Florida tomato, nightshade or pepper plants.
6. Infestation does not reduce the keeping qualities suffi-
ciently to keep the unsound tomatoes from the retail market.
7. All material remaining in the field after the crop is har-
vested should be carefully plowed under in order to reduce the
danger of the patch becoming a resevoir for infestation of a
near-by or a succeeding crop.


FLORIDA ENTOMOLOGISTS WILL BE INTERESTED IN
LETHANE 440
Synthetic Contact Insecticide
The killing agent in this new type of spray is an organic thiocyanate.
Lethane 440 has shown itself to be outstanding for the control of
cottony cushion scale, mealy bugs and other scales; red spiders and
mites; white fly, leafhoppers, thrips and aphis. For information
write to
ROHM & HAAS COMPANY
222 West Washington Square Philadelphia, Penna.





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Carefully Executed
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Pepper Printing Company
Gainesville, Florida


We recommend the goods advertised in The Florida Ento-
mologist. Please mention Entomologist when you write our
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Uhe
FLORIDA ENTOMOLOGIST
Official Organ of The Florida Entomological Society,
Gainesville, Florida.

VOL. XX NOVEMBER, 1937 No. 3

J. R. WATSON, Gainesville........-----.......................................-.. Editor
E. W. BERGER, Gainesville-..--......--.......................Associate Editor
J. W. WILSON, Lakeland---..............-....--.......-- ..Business Manager
Issued once every three months. Free to all members of the
Society.
Subscription price to non-members is $1.00 per year in ad-
vance; 35 cents per copy.

THE INSECT DEPREDATORS OF PURSLANE
(Portulaca oleracea L.)
H. J. ROMM, Tuskegee, Ala.

INTRODUCTION
It is only within relatively recent years that workers have
begun to turn their attention to a study of the part played by
weeds in the economy of our noxious insects. The need for
such information is greatly increased by our knowledge of the
role of insects and weeds in the dissemination of the various
maladies of cultivated plants. Thus, Lindford (71) has shown
that Emilia flammea Cassin, a weed common in pineapple fields
of Hawaii, is the "reservoir" for the serious disease of pine-
apples known as Yellow-Spot, and that the onion thrips (Thrips
tabaci Lind.) transmits this malady from Emilia to pineapples.
Drake, Harris, and Tate (26) proved that aphids, commonly
feeding on purslane and other weeds in the onion fields of Iowa,
often in their wanderings from plant to plant stop to imbibe
the juices of the onion and by so doing may become the vectors
of that peculiar disturbance, Yellow Dwarf of onions. Their
studies show that it would be impossible for these aphids to
live and complete their development on the onion; yet they are
the sole natural vectors of Yellow Dwarf.
Not only is the relation between insects and weeds important
in the spread of plant diseases; this relation is equally important
to cultivated crops in many other ways. This is brought about
in part by common weeds serving as favorite hosts, thereby









THE FLORIDA ENTOMOLOGIST


harboring insects and promoting undesirable insect populations.
So efficient are weeds in this respect that their insect depre-
dators, because of a diminishing food supply, often shift their
attacks to adjoining cultivated crops and there do untold damage.
There are countless examples which will illustrate the intricacy
of this relationship between insects, weeds, and crop plants.
Davidson (21) gives a very striking example of certain aphid
species which, in their annual cycle, will migrate in the autumn
from a group of numerous, unrelated, herbaceous, summer host-
plants to a few, closely related woody-stemmed winter hosts.
In the spring they migrate back to their summer hosts.
In grassy and weedy gardens, where cutworms are wont to
lay their eggs, considerable damage is done to cultivated plants.
The cutworms migrate to the cultivated plants when their nat-
ural food supply is exhausted.
Forbes (44) has shown that the corn-root aphid is dependent
in the early spring upon such weeds as purslane, ragweed, fox-
tail, smartweed and crab grass before corn is planted. Decker
(23) found that along the margins of fields, cultivated crops
like corn, during certain seasons, are attacked by the common
stalk borer, Papaipema nebris Guenee, after the larvae have
begun their development on grasses or weeds.
To encourage the increase of insects in the interest of weed
control would at first appear to be contrary to the general prin-
ciples of pest suppression; but there are some records of such
which are both interesting and convincing. For example, the
Russian thistle is usually present in great abundance in Canada
in many sections where clean farming is not practiced. How-
ever, this noxious weed does not cause undue alarm because
the growers have learned that the sugar beet webworm, Loxos-
tege sticticalis Guenee, will check its spread. The sugar beet
webworm will also feed upon cultivated plants and many weeds,
including purslane, when Russian thistle is not present.
Again the use of insects in combating weeds finds a classic
example in Australia. Here the cactus is an important plant
introduction. Within recent years it has become established
in New South Wales and Queensland, spreading over sixty
millions of acres and causing great alarm by forming impene-
trable thickets over thousands of square miles of territory.
Certain insects which feed upon the cactus in Mexico and South
America have now been introduced into Australia for the ex-
press purpose of controlling this dangerous weed. Latest








VOL. XX-No. 3


published reports show that almost unbelievable results in re-
claiming this land have been obtained from the use of these
insects.
Metcalf and Flint (84) cite the work of Glick, who in an
unpublished manuscript records that a species of sawfly elim-
inated purslane from a ten-acre field of onions, although neigh-.
boring fields were much troubled with this weed. On numerous
occasions the author observed the purslane sphinx, Celerio
lineata Fab., feeding on the foliage and stems of purslane,
keeping it from seeding. According to Hyslop (63) Centorhyn-
chus marginatus Payk., was introduced accidentally into this
country. It feeds upon the seeds of the noxious dandelion,
Taraxicum officinale Web., often destroying one-quarter of the
seed. Marcovitch (77) reported that milk vetch (Astragalus
canadensis L.), a very common weed of Minnesota, is kept from
becoming a weed of the first rank by its insect enemies. The
agromyzid fly which feeds upon lantana and keeps it from seed-
ing in Queensland was introduced into Hawaii by Koebele for
the purpose of controlling the spread of this plant.
Weeds at times may be thought of as being beneficial in that
they harbor numbers of parasites which develop upon their
insect depredators. These parasites are often of great value
in destroying many other insects which might become very
destructive to crop plants. In the writer's experiments several
white-lined sphinx moth larvae were taken from purslane in
the field and caged. Later they pupated but the adults never
emerged, for they had been parasitized by certain hymenop-
terous forms. Two of the pupae were dug up and examined.
They contained well-developed parasitic larvae. This illustra-
tion has been given to show the relationship between weed
feeders and the parasities in their control. The control of plant-
feeding insects by other insects is very complicated. It has
been found that many parasites increase to such a degree as
to prevent any appreciable damage.
From what has been said above it may be seen that a study
of the relationships between insects and weeds may often be
of great importance. In this paper the author has confined
himself to a study of the insects which feed upon the herbaceous
weed, Portulaca oleracea L., or common purslane. Much use
.was made of the literature on the subject in order to compile
as complete as possible a list of those insects feeding on it.








THE FLORIDA ENTOMOLOGIST


THE PLANT (Portulaca oleracea L.)
The species Portulaca oleracea L., is a common plant of
India-its natural home. It occurs over Europe and North
America, being especially abundant in gardens. Records show
that purslane was carried westward from Asia to Europe, and
for centuries it was used as a salad and pot herb. This plant
was observed in Massachusetts as early as 1693. Since then
its spread has been very rapid. This rapidity of spread is
due in a large measure, one writer has said, to the carelessness
of the early Pennsylvania Germans, who were very fond of it
as a vegetable.
Purslane is a procumbent annual, with mostly alternate,
oblong-cuneate leaves about one-half inch long. The flowers
are yellow, sessile and axillary. The seeds are black.
Some authorities have called purslane a "Cosmopolitan
Weed" because of its wide distribution. It is not uncommon
here in the United States to find it in cultivated grounds around
dwellings and also in waste places.
Purslane has some direct economic value. Knight (69) says
that the juice from its leaves will relieve swelling and pain
inflicted by the hairs from the body of the white-marked tussock-
moth larva. It is also of value as food for hogs, a purpose to
which quantities are devoted. The seeds are used in medicine.
SUMMARY AND LITERATURE
A careful and comprehensive search of the literature has
failed to disclose any previous lists dealing specifically with
insects feeding on purslane. However, there are many isolated
records in various text books, taxonomical works, catalogues,
and host-plant indices. It has been the problem of the writer
to gather these, to supplement them with his own field observa-
tions and rearing records, and to organize and present the whole
in a detailed and usable list. All told, eighty-three species, dis-
tributed in their Arthropodan orders, are recorded in this paper.

INDEX TO THE FLORIDA ENTOMOLOGIST
An index to volumes 1 to 19 inclusive of the Florida Ento-
mologist is now in preparation. This index contains a table of
contents arranged by volumes and an index of the insects by
specific and varietal names. This index is to be sold at 75c a
copy. Orders should be sent to J. W. Wilson, Business Manager,
Lakeland, Florida. Subsequent volumes will have an index in
the last number of each volume.







LIST OF INSECTS FOUND ON PURSLANE


Genus

COLEOPTERA-
Chrysomelidae
Diabortica

Diabortica
Diabortica

Disonycha
Disonycha
Disonycha
Graphops
Systena
Curculionidae
Centrinaspis

Ceutorhynchus
Baris
Hyperodes

Sitona

Sitona
Scarabaeidae
Lachnosterna
DIPTERA-
Agronyzidae
Phytomyza
Anthomyiidae
Hylemyia
Cecidomyiidae
Campylomyza
Joannisia
Empididae
Platypalpus


Scientific Name
I Species


duodecimpunctata (Fabr.)

longicornis Say 37, 38, 39,* 84, 137
vittata (Fabr.)

crenicollis (Say)
caroliniana (Fabr.) 9, 151
mellicollis (Say) 27
pubescens (Melsh.)
taeniata (Say)

perscitus Hbst.

portulacae Marshall 79
portulacae Marshall 79
echinatus Dtz.


hispidula Fabr.

flavescens Marsh.

rugosa Melsh. 43

palliata Coq. 46

cilicrura Rd.

sp. 132
sp. 132

crassifemoris Fitch. 132


*NOTE: The number appearing after each species


Part of Plant Affected


Leaves

Roots
Leaves

Leaves
Leaves
Leaves
Roots
Leaves

Tunnels roots and stem

Tunnels leaves
Roots and stems
Leaves

Leaves

Roots

Roots


Mines the leaves

Sprouting seeds

Roots
Roots

Roots


Observations




A few were observed eating small
holes in the leaves.

Observed in large numbers eating
small holes in the leaves.
Many were found.

A few were taken.
A number were found feeding on
the foliage.
A few of the larvae were taken
from the stem.


A few were taken from
plants.
A few were taken from
plants.
Taken from a number of
plants.


caged

caged

caged


refers to the reference in the bibliography.


(To be continued)


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