The Venomous Snakes of Panama

Accession number 2003.052.046
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Title:
The Venomous Snakes of Panama
Physical Description:
Mixed Material
Language:
English
Creator:
Norman W. Elton, M.D.
Donor:
Family of George & Mayno Walker ( donor )
Publisher:
The Safety Branch, Canal Zone Government-Panama Canal Company

Subjects

Subjects / Keywords:
Poisonous snakes
Gorgas Hospital (Ancon, Ancon, Panama)
Spatial Coverage:
Panama -- Central America -- Panama Canal Zone

Notes

General Note:
Item received on 5/26/2011

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Holding Location:
Panama Canal Museum Collection at the University of Florida
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Public Domain Presumed (e.g. expiry of copyright term): This item is presumed to be in the public domain. The University of Florida George A. Smathers Libraries respect the intellectual property rights of others and do not claim any copyright interest in this item. Users of this work have responsibility for determining copyright status prior to reusing, publishing or reproducing this item for purposes other than what is allowed by fair use or other copyright exemptions. Any reuse of this item in excess of fair use or other copyright exemptions requires permission of the copyright holder.
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accession number - 2003.052.046
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PCMI011531:00001

Full Text



THE VENOMOUS SNAKES OF PANAMA

by

NORMAN W. ELTON, M.D., Chief, Board of Health Laboratory, Gorgas Hospital

0
PUBLISHED BY THE SAFETY BRANCH, CANAL ZONE GOVERNMENT-PANAMA CANAL COMPANY
0

PART I

SNAKEBITE: GENERAL DISCUSSION


If one does not fear lightning one need have no fear of
poisonous snakes, for it has repeatedly been demonstrated
statistically that one's chances of dying from snakebite are
no greater than those of being struck by a bolt of lightning.
Furthermore, the mortality among people actually bitten by
poisonous snakes in Central America in Clark's Statistics is
less than 10 percent. This unusually low mortality in the
tropics is readily understandable because our snakes are
generally well-fed and do not hibernate. These two factors
tend to decrease the potency of their venom.
The commonest situation likely to result in being struck
by a poisonous snake is an encounter with one that has just
swallowed a meal (a lizard, a rodent, a bird) and, having
failed to find cover after its night of successful hunting is so
distended with its food ball that its belly plates are spread
apart, and it is unable to move except with great difficulty.
This snake will strike in self-defense when moese.
However, in killing and swallowing its meal it has used up
most of its venom, and for several days the refill in its
poison glands will be very dilute and of low toxicity. It is,
therefore, most reassuring to. note that the offending snake
is distended with a food ball, for the prognosis is then very
favorable.
Most of the bites, as Clark has shown, involve the foot
and ankle and the hand and wrist. The protective coloring
of many snakes may result in a bite on the buttocks, unless
one is very observant at times. The foot and ankle bites
occur because vipers strike very low (even the King Cobra
strikes the elephant on the toe-although the cobra is not
a viper-because it "bows" from its "stand" to strike). The
hand and wrist bites are incurred largely in climbing a
slope, when the snake is located on the higher ground.
As a rule poisonous snakes do their best to get out of the
way of the traveler in the bush. Exceptions occur in the case
of the food-laden ofie which cannot get out of the way,
and also, unfortunately, in the case of the pregnant female
during the spring breeding season, which, laden with
young or eggs, has found difficulty in obtaining food, with
the result that her venom has become highly concentrated
from enforced starvation. Being unable to cruise about, she
becomes highly defensive and quite aggressive-in short,
really "muy malo." Bites from long-starved snakes are very
serious and usually fatal.
In going into the bush it is a cardinal rule not to travel
alone. Accidents can happen,-as well as snakebites, and
groups should never comprise less than three or four


individuals in a party. It is a well known jungle axiom that
"when troops move in, snakes move out." Natives, traveling
alone and poorly shod, are the principal victims of snake
bites. Most of them, when traveling this way carry a
shotgun, if they have one, for such encounters.
When a jungle camp is occupied for any length of time,
food waste will attract rodents, and rodents will attract
snakes. Since snakes hunt at night, some precautions will
be advisable. For example, before putting one's foot outside
of one's wickiup, spot the ground with a flashlight first,
just to make sure the coast is clear. When the time comes
to break camp, in handling boxes or piles of supplies take
care to note whether or not a food-laden snake may be
resting under cover of the material being moved trying
to keep out of the way while digesting its meal.
The treatment of snakebite in an emergency situation
can be-made quite simple and effective. In the first place,
the snake should be identified, caught, and at least its head
with 2 inches of its neck should be secured for proper
identification in case it is considered advisable to administer
antivenin later on. If the snake is not poisonous, treat the
wound as a potentially infected abrasion or laceration,
preferably by immersion for 20 to 30 minutes in hot soapy
water. If the snake is poisonous, then apply mouth suction
at once to the region of the fang holes, encompassing the
area widely with the teeth and lips and milking the contents
of the fang channels in much the same manner as a suckling
infant at the breast. The mechanism involves gentle massage
with the teeth as well as suction. As an adjunct a tourniquet
should be applied to the upper arm or thigh, but tight
enough to shut off only the veins, and not tight enough to
stop the pulse in the wrist or ankle. This will block the
venous and lymphatic absorption of the venom and by
keeping the arterial blood pressure sustained, will tend to
flush out the venom through the fang channels.
There are very good reasons why incisions at the site of
the fang punctures should not be attempted. Viper fangs
are long, curved and hollow, and the opening through
which the venom is ejected is close to. the tip of each fang.
The ven6m emitted from the fang will not be in the vicinity
of the puncture holes on the skin, but will be deep in the
tissues and off to one side, depending on the direction from
which the strike was made. If these fang channels are left
intact venom can be drawn out by the mouth suction
method to the skin surface without further absorption, but
if the fang channel has been interrupted by incision, not






only will the withdrawal of the venom be- made more
difficult, but also fresh raw tissue surface area will be
exposed to facilitate additional damage and absorption
without in any way assisting in the removal of the venom
from the deep pockets under the skin.
The mouth method ofsuction and "milking" is far
superior to any cup suction. Most cups have too narrow
a diameter and not only do not include both holes, if both
fangs pierce the skin, but tend to compress the 'fang
channels, when they run in oblique directions, and block
the outflow of theooze from the deep venom pockets.
Venom when swallowed is harmless. If one's mouth is in
good condition, without abrasions, open ulcers, or bleeding
gums, mouth suction will not harm the person performing it.
However, if there is any apprehension relative to the
possibility of absorption of venom through a break in the
mucous membranes of the mouth, then a sheet of thin
latex rubber should be placed over the skin before applying
the mouth suction in order to protect the operator. This will
not impair the efficacy of, the treatment and a rubber sheet,
or material from which it can quickly bemade, should be
carried as a part of the necessary individual equipment
taken on jungle trips. It is easily carried in a waterproof
matchbox.
Before undertaking a more detailed discussion of the
several species of poisonous snakes of Panama, let us
recapitulate the procedure to be observed in case of snake
bite.

1. PREVENTION OF SNAKE BITE:
a. Do not travel alone in the bush: a companion may
see the snake that you do notfnotice.
b. Be well shod. At least do not wear low shoes. Tuck
trousers into boots and have trousers loose and baggy.
c. Be watchful when using your hands in climbing or
in clearing brush. The native who knows how to use
a machete, has a bent stick in his left hand to hold
branches and small vegetation prior to clipping it with
his machete.
d. When you see a snake, freeze in your tracks until you
can estimate the situation. The snake will not attack
you, since he will beas much surprised and disturbed


as,-you are, and the chances will be 4 to- I that he is
a nonpoisonous type.
e. If alone and proceeding through snake country, make
a lot of noise 'to give the snakes a chance to get out
of your way.
f. Carry in your equipment a rubber sheet (thin latex)
and a piece of rubber tubing for use as a tourniquet.
g. Be especially watchful at night. This- is when the
hungry snakes are hunting rodents. They will not be
hunting you, but there might be a misunderstanding.

2. ACTION IN CASE OF SNAKE BITE:
a. Identify snake. Is it a poisonous species? Look for the
snake in the immediate vicinity as snakes with food
balls cannot go far. Have someone in the party get the
snake if you have a burlap bag to put it in. Otherwise
obtain its head andabout 2 inches of neck for later
identification. The severed head of a poisonous snake
can still produce a bite, so handle it carefully. Boa
bites are razor-like, but quite clean, and require the
same treatment as ordinary wounds.
b. If the snake is of a poisonous species, find out if it
has a food ball. If it has, then the person bitten has
much less to worry about, since the venom will be
of low toxicity.
c. While someone is taking care of the snake, the person
bitten can apply hi own mouth suction, if it is an
accessible hand or wrist bit. If it is an ankle or foot
bite, someone else in the party will have to be the
operator. A tourniquet on the upper arm or thigh, not
tight enoughI to stop the pulse, should also be applied.
There may be only one fang hole, since the snake
may have shed one of its fangs before the replacement
fang was ready for use.
d. Take the patient without delay to the nearest medical
installation, but keep up the mouth suction inter-
mittently on the way. Release the tourniquet for a
couple of minutes every 20 to 30 minutes to prevent
damage from the tourniquet itself. Present the snake,
or its head and neck, to the doctor for proper identifi-
cation, with information as to the presence or absence
of a food ball.


PART H


CHARACTERISTICS OF THE POISONOUS SPECIES


. Regional snake faunas of the geographic divisions ,of
the world vary in the different localities. In each area the
principal effort should beIdirected toward acqumiing a
familiarity with the poisonous species, since they are usually
less abundant than the others and of more importance to
man. They are also better known by local or common names
than the more abundant and varied relatively harmless
species.
In our part of the world there are three main families
of poisonous snakes; namely, the pit vipers, the corals, and
the sea snakes.


Only in the Western Hemisphere do the vipers all have
pits. This is a recess on the outside of the upper jaw between
the nostril and the eye, which, as Dr. Harold Trapido points
out (based on the work of Noble and Schmidt), is a tem-
perature-detecting-qrgan that provokes their strike at the
warm-blooded animals they seek as prey when close enough
to detect the body warmth of the passing victim. Trapido
also believes that the pit-like structures along the side of
the low er Jaws of the constrictors (boids) may perform the
same function. Even though pit vipers are blinded with
blackened collodion and their tongues removed, they will






strike at an electric light bulb covered with opaque black
material only when the filament is hot.
Vipers have long retractile, hollow, curved fangs situated
in the front of their upper jaws. These fangs are thrown
down and forward when in striking position, and are
concave to the rear. When the strike is made and the fangs
pierce the victim, there may be a slight tug backward, and
the contraction of the venom glands ejects the venom out
of the hole in the fang just above the point and to the front,
where a small space in the victim's tissues has been made
by the slight backward tug of the fang. Viper fangs may
attain a length of 11/4 inches in the large fer-de-lance or
bushmaster.
Accurate identification of poisonous snakes involves a
careful study of each species and of the individual variations
within the species. The young are often different from the
adults. There is hardly any rule of thumb that can be
applied indiscriminately. Facial pits are of considerable
importance, especially in the Western Hemisphere, for
recognition of the vipers, but many of the Old World vipers
lack pits. The slit pupil of the eye can be demonstrated also
in harmless snakes, and is a group characteristic of those
with nocturnal habits.
Bushmasters have a double row of plates under the tail,
though in other venomous snakes this row of plates is often
single. Snakes that have new coats after shedding look quite
different from others that are about to shed their old skin.
The pit vipers of Central America consist of seven main
species: the fer-de-lance, the bushmaster, the tree vipers,
the hog-nosed vipers, the mano-de-piedra, Godman's viper,
and the tropical rattlesnake.

THE FER-DE-LANCE
The fer-de-lance, a member of the Trimeresurus family,
is also known as the terciopelo ("velvet skin"), the barba
amarilla ("yellow beard"), and the equis (because of the
x-like design of its body markings). This is a snake which,
although found in the jungle up to 2,000 feet in altitude,
commonly frequents lowland plantations in search of the
rodents that live on the abundance of fruits. In the planta-
tions the "equis" has come to be regarded as a benefactor
of man, because of its controlling effect on the rodent
population. This snake is slender, dark, often black, with
light colored somewhat light-yellowish to light-gray x-like
designs on its back, and averages, when fully grown, about
5 feet in length, rarely attaining 6. feet. Its head is lancet-
shaped, whence it has derived the name "fer-de-lance."
The females are viviparous, giving birth to some 45 to 70
lively and very aggressive youngsters in each litter. These
newly born snakes are just as dangerous as their parents,
for their foo (moths and insects) is hard to get, their
competition among themselves is keen and their venom
concentrated. Because of the trouble they have in feeding
they are liable to be encountered still active in bushes and
grass after sunup, a time when most vipers seek cover.
This was apparently the first lancet-headed new world
snake observed by the European settlers, and for a long
time was thought to exist only on the island of Martinique,
and in South America. Later it was found to have a much


greater range, including all of Central America. Other
species of lancet-headed vipers were soon discovered.


Baby fer-de-lance are lighter in body color, and somewhat
difficult to distinguish from some of the harmless snakes
of the same size. This is why most of the people who have
been in the bush always regard such small snakes with
suspicion, and consider many innocuous types as dangerous
"equis" until proven otherwise.
The fer-de-lance has come to be regarded as the most
dangerous snake in the Panamanian jungles, chiefly because
it is the commonest of the vipers. The speed of its strike
is so fast that the eye can hardly follow it, although its
striking range is very short (6 to 10 inches). It is said that
the mongoose which invariably masters the cobra, has only
a 50-50 chance with the fer-de-lance.
As with most snakes, the sex of the "equis" is hard to
determine without disection. Not infrequently in the spring
of the year a "well-fed" snake taken into captivity may
surprise its keepers by giving birth to young in great
numbers. This happened once in a scientific institution in
Panama, for one morning it was discovered with dismay
that the "well-fed" Snake, a fer-de-lance, had grown very
thin during the night, and the vicinity of the cage was
swarming with about three score lively little "equis" with
a ravenous appetite. A real snake hunt ensued.
A frequent heckler's question asked of a person expound-
ing about snakes may be "How do you tell the males from
the females?" Lyle Womack has a good answer to that one
in the reply "That, my friend, is a question of great
importance to the snakes, but not so much concern to us."

THE BUSHMASTER
This 'oval-headed, longest and heaviest viper of the
American Tropics, averages about 7 feet in length, and
would weigh about twice as much as a fer-de-lance of the
same length. Although specimens have been reported up
to 14 feet in length, they have not yet been brought in here
for confirmation. It is the second largest poisonous snake
in the world, second only to the king cobra, and frequents
rocky forested country. Its general body color is tan, with
a black saddle-like pattern on its back.
Although a powerful snake, and much slower than the
fer-de-lance, it must be handled carefully when captured,
because its back is easily broken, and many valuable speci-
mens have been spoiled in this fashion when taken alive.
The bushmaster does not do well in captivity, invariably
dying in a short time, and seldom will it be found in any zoo.
The scientific name of this snake is Lachesis Muta. It is
also known as the "verrugosa" or "warty one," and as the
"cascabela muta" (silent rattle snake) because of the spine
on the tip of its talwhich may vibrate among dry leaves
so as to simulate the sound of raffles when it is alerted or
nervous. It is also sometimes called "mapana."
Bushmasters lay eggs, about 10 tO 14 at a time, and those
that surive after the hawks, rodents, coati-mundi, and
other predators of the jungle have eaten what they find,
hatch into young snakes that immediately disappear under-
ground, where they frequent the brosof the rodents,
living in turn on their young.
Apparently whnthey beome too large to maneuver
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masters have seldom been captured or even seen beyond
the egg stage.
It would seem appropriate to stress the rarity of the
occasion when one will see a bushmaster. Yet, I recall a day
in 1943 when Dr. Clark was stressing this very point to a
group of naval officers undergoing jungle training by
Maj. Cresson H. Kearny, of the Panama Mobile Force, on
the Madden Forest Highway. That same afternoon Kearny
took them off on a compass course cross-jungle from Las
Cruces Trail, and they returned a couple of hours later with
a live 7-foot bushmaster. Unfortunately its back was broken
and it died over the weekend.
This brings up the point of snake collecting. Using a
loop-on-a-pole catching device, the live snakes should be
deposited in a good burlap bag. Thus they may be carried
satisfactorily and comfortably, preferably with the bag tied.
For some reason or other they cannot endure a horseback
ride, frequently dying en route when carried in this manner,
but they will survive an automobile ride.
The best place to take them for study and observation
at present is the Gorgas Memorial Laboratory, Avenida
Justo Arosemena, located between the Panama Hospital
and Santo Tomas Hospital in Panama City.


HOG-NOSED VIPERS
The small hog-nosed vipers of Panama are true pit vipers,
definitely poisonous, and not related generically to their
harmless namesake in the United States.
They are of two species: (1) Trimeresurus lansbergii of
the Pacific side, and (2) Trimeresurus nasutus of the
Atlantic side. Their common names are patoca or tamaga.
They range in length from 12 to 18 inches. The tipped-up
nose of the Atlantic species is more prominent than that of
its Pacific relative. They are dark brown or black with faint
brick red rhomboid markings on their backs.
As a ground snake of the sabanas more than of the forest,
it is less apt to strike than the fer-de-lance, and few bites
have been reported by these species.


TREE VIPERS
There are three species of tree vipers, the commonest
being Trimeresurus schlegelii (horned palm viper, eyelash
snake, bocaraca, toboba de pestamas, oropel, or sleeping
gough). This is a small, sometimes rather stocky, snake,
10 to 14 inches in length including its prehensile tail
which enables it to live in trees and bushes, where it feeds
principally on birds.
The drawing of its head (see illustration) hardly does it
justice, for its expression is that of unmasked malice in
pure form. Their colors vary from olive green or butter
yellow, with specks of black, to almost black with a pinkish
pattern over the back, even in littermates.
Their prehensile tails and scales above the eye, standing
out as small horns or eyelashes, make identification easy.
Common in cacao plantations, they may b encountered in
the felling of trees and bushes. Several were collected by
the M obile Foc tros in the Pifia area during the war.
Their venom spells instant death to birds. Clark tells of


seeing one strike a bird only a glancing blow. The bird fell


to the ground, and by the time it could be located and
picked up it was stiff with rigor mortis. Clark knows of only
one instance of a workman being struck on the shoulder
near the neck. After some discussion at the time (facetiously)
of where to apply a tourniquet for such a location, mouth
suction was applied, and the man recovered uneventfully
without specific treatment.
There are two other species of tree vipers, without eye-
lashes, which so far have been found only at elevations of
4,000 to 6,000 feet.
One, Trimeresurus lateralis has light stripes along its
sides, and the other, Trimeresurus nigroviridis nigroviridis
has powdershot black specks scattered throughout the green
body background. They are about 18 to 30 inches long
and both are green in color.

THE "JUMPING SNAKE"
This is another dart-headed snake, about 10 to 20 inches
in length, with a very heavy body. The body pattern
resembles that of the bushmaster, but is of a double saddle
and stirrup pattern in pairs at close intervals.
Its strike is so vigorous that it may stir up a cloud of
dust as its short powerful body pulls away from the ground.
This is how it derives its common names, "jumping snake,"
"timbo," and "mano-de-piedra."
They are found in rocky elevated places; one large
individual having recently been brought in from the East
Ridge. Its scientific name is Trimeresurus nummifer.

THE TROPICAL RATTLESNAKE
The tropical rattler, Crotalus durissus, is by far the dead-
liest of all, but none have as yet been collected in Panama.
Only one is now a collector's item at the Board of Health
Laboratory, and that was presented by Douglas March
from his Honduras collection. Its colors have long since
faded out in formalin.
It is alleged to exist in the dry tablelands of the Provinces
of Chiriqui and Veraguas, where it is zealously protected
by the natives of the Bocas del Toro region.
To these Indians the tropical rattler is a religious symbol
and an economic asset, for, depending on its venom for
obtaining their food, they make up a mixture of liver paste
and venom with which to tip their hunting arrows and
spears.
They allow no white intruders to enter their domain, or to
molest their snakes. Explorers in that area, once believed
uninhabited, but now found by air observation to be under
intensive cultivation, are no more welcome than were the
Conquistadores; and to those Indians contemporary man is
still as undesirable and treacherous as they found by bitter
experience to be characteristic of the Conquistador.

GODMAN'S VIPER


This is another small thick ground viper, black in color,
and about 18 to 22 inches in length. Natives say that they
seldom strike a person, and there are no records of bites.
They have been found at about 4,000 feet elevation.,






THE CORALS
I have hardly mentioned the coral snake up to this point.
The coral minds its own business, usually tolerates gentle
handling if one is indiscreet enough to pick one up, and
asks only to be let alone.
It would, however, be very dangerous to step on one
inadvertently with bare feet, for it will resent being hurt.
It always reminded me of the easygoing cocker spaniel
of the poisonous snake family. Being a burrowing snake,
few accidents have been caused by it.
There are in all about 11 recognized species of true corals
in Panama, many of them very small, and not all tricolor.
The common true coral, ranging from 10 to 20 inches in
length, is tricolor, and may be described as like a newspaper,
"black and white (sometimes yellow instead of white), and
red all over." The basic body color is coral red with black
bands bordered by white (or yellow) at intervals.
The eye of the poisonous tricolor corals is very small, in
contrast with the larger eye of the nonpoisonous tricolor
false corals.
The coral's scientific name, as a member of the elapidae,
is micrurus, of the given species, such as Micrurus nigro-
cinctus nigrocinctus, which is the one commonly seen. It is
also know as the harlequin snake.
The coral in Mexico is known as the "20-minute snake,"
for the victim is supposed to be a goner 20 minutes after
being bitten by one.
However, the coral is not well-equipped for biting, and
its fangs are short, grooved, and fixed, placed so far back in
its upper jaw that it has to batter at its target fast and
furiously, like a sideswiping trip hammer, beforeit can get
a grip. Then, when it does get hold of a fold of skin, it hangs
on like a. bulldogand chews like a cobra to instil its venom.
It is capable of causing a serious bite only under such
favorable circumstances. Needless to say, since its fangs are
so short, and its bite so superficial, incisions would hardly
be indicated in treatment. Regular snakebite technique, as
outlined in Part I of this discussion, should suffice.

THE SEA SNAKES
In the Pacific, ranging from the shores of Panama to the
Indian Ocean, there are some 50 species of sea snakes,
from 1 to 3 feet in length.
These true reptiles do not molest man unless they happen
to be caught in a net with a lot of fish, or are washed up
on a beach, and handled,
Related to the corals, kraits and cobras, their venom is
a highly potent neurotoxin. Although they have often been
seen washed up on the shore of the causeway leading to
the attached islands of Naos, Culebra, Venado, and
Flamenco, and on the beach of San Jos6 in the Perlas group,
no one has ever yet been bitten by one in Panama. Clark
tells an amusing story of a trip he made down the coast.
There being only One panga to use for going ashore, he
dove in and started to swim the 200 yards to the beach.


He had not been swimming long before the rest of the
party on the boat began yelling at him and pointing to the
water. Thinking it some joke, he waved casually and con-
tinued swimming to the shore. When he mounted the bank


on the beach, they were still yelling and pointing to the
water. He then looked himself, and to his chagrin realized
that he had swum through a school of thousands of sea
snakes without ever feeling the touch of one of them.
"Well," he grunted, "They're just looking for shrimp and
small fish to eat." But he didn't swim back to the boat
to prove it. These snakes have never been known to attack
swimmers.
The common sea snake of the Panama coast is Pelamy-
drus platurus, a black snake with orange patterns on the
side and belly, having a tail vertically flattened like an eel
or an oar blade.
It is at times exceedingly abundant in Panama Bay
Length is about 12 to 24 inches.

THE NATURE OF SNAKE VENOM
Venom is actually a potent saliva derived from the
parotid gland of the snake which, in man, is the salivary
gland that becomes swollen when we have mumps.
The use of venom defensively is a secondary adaptation,
for its primary use is to kill and digest the prey. Hence a
snake uses up most of its venom in killing and swallowing
its victim.
Venoms are complex proteins of high toxicity and their
mode of action is mainly of two and possibly three types:
one, an effect on red blood cells and the walls of blood
vessels, causing dissolution of the red blood cells and
hemorrhages from the damaged capillaries; another, acting
on the nervous system, inducing paralysis of muscles,
especially affecting those nerves that operate the muscles
having to do with respiration; and a third consisting of a
general digestant action on all tissues, especially after the
local death of tissue resulting from the other effects.
Kenneth Vinton has pointed out that this digestant action
of venom will actually operate favorably during suction
treamtent of snake bite by widening the fang channel and
facilitating the outflow of tissue juice containing the venom
from the site of injection.

CONCLUSION
An apology seems in order for my pretense at knowing
something about snakes. I have enjoyed an association with
a number of outstanding naturalists, physicians, and
biologists during my periods of service in Panama, among
whom the most stimulating has been Dr. Herbert C. Clark,
and many of the ideas I have presented are really his.
My contribution rests mainly in the dissemination of
this information during my service as Mobile Force Surgeon
in 1942-1944, when I covered some 400 mies on foot on
patrols, hikes, and inspection trips, and assisted Maj.
Cresson H. Kearny in his work of preparing troops for
operations in the jungles.
All who are interested in snakes in a scientific way,
I should like to refer to a number of people who are far
more expert than I, such as James Zetek, at the Barro
Colorado Biological Area, Dr. G. B. Fairchild, and Dr.


Harold Trapido, at Gorgas Memorial Laboratory, to
Kenneth Vinton at the Canal Zone College and to the
Museo Nacional, in Panama City, where there is an
excellent collection.


















































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