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The idea that a venomous snake can strike its full length or even a 
greater distancé is cnother peruler But erroneous belief, - Whenna snake 
/Strikes from its usuel s—-shepecd posiéion, the énterior nalf of the hody, 
whicn is thrown forward, must be free from coili In striking, the snake 
simply straightens out the S-shaped curvese It does not have to be in 
this position to strike, for observation has shown that when irritated 
most of our poisonous snakes can strike for short distances from almost 
any position. The western diamondback rattler, when excited, frequently 
raises its head and the S-shaped loop 10 to 15 inches above the ground, 
from which position it strikes sidewerd and downward. When this rattler 
is lying coiled with its head resting on its body, it is able to strike 
almost vertically upward. The greatest length of stroke is about three— 
fourths the length of the snake, but few snakes strike more then half 
their length. 
VENOMS OF POISONOUS SNAKES 
Venom is a: secretion of a supralabiai gland tnat resembles in its 
development the parotid (a salivery) gland in mammals, It is composed of 
50 to 70 percent proteins: the chief remaining components are water and 
carbohydrates, with occasional admixtures. of abraded epitheliel cells, or 
saprophytic micro-organisms, while salts such as chlorides, phosphates of 
calcium, magnesium, and ammonium occur in small quantities. The reaction 
of venom to litmus is usually acid; in some cases, neutral. The venoms of 
the different species of. poisonous snakes differ to a greater or lesser 
degree, although all venoms are multiple in nature, that is, they contain 
several toxins that act independentiy of one another. Warm—blooded animals 
are usually more susceptible to venom than cold-blooded ones. Dried venom 
retains its original toxic properties in unaltered strength and quality for 
an indefinite period. Dr. S. Weir Mitchell found that venom kept dry for 
23 years was unaltered in these respects. When fresh, the venom of a snake 
is a somewhat viscid fluid of yellowish color. 
The effect of venom on the victim is due to the complicated action of 
several toxic elements, of which neurotoxins and hemorrhagins (explained 
later) are the most important. Neurotoxins have a destructive action upon 
the nervous system and play the most important part in producing the death 
of a victim of venom poisoning. They are present in relatively large pro- 
portions and are the chief death-dealing factors in the venom of the coralor 
harlequin snakes (Micrurus and Micruroides), which belong to the cobra 
family (Elapidae). In contrast, rattlesnakes (Crotalus and Sistrurus) and 
moccasins (Agkistrodon) of the. family Crotalidae produce neurotoxin in com— 
paratively small Quantities. The venom of the cotton-—mouth water moccasin 
contains more neurotoxin than that of the rattlesnake, and consequently its 
paralytic effect on the respiratory center and motor nerves is stronger. 
This toxin not only breaks down the nuclei of the ganglion (nerve center) 
cells, but produces granular disintegration of the sheath (myelin) and frag— 
mentation of the conducting portions (axis cylinder) of the nerve fiberS. 
These neurotoxins offer a high resistance to heat and retain their toxic 
properties after prolonged tréatment with alcohol. 
The hemorrhagins constitute the chief toxic elements of rattlesnake 
venom and have a solvent action on the endothelial cells composing the walls 
of the blood and lymph vessels, particularly the smallest of them known as 
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