its head. The cotton-mouth is commonly confused with the brown water snakes 

 of the genus 7\[atrtx, which bite readily but are not poisonous. It is found 

 from Indiana and Illinois southward. 



In the southern states the coral snakes are occasionally turned up by the 

 plow or more rarely seen above ground. They are nocturnal members of the 

 cobra family and, but for their small size, would be most dangerous. The 

 poison, like that of the dreaded cobra, acts on the nervous system. The hollow 

 poison fangs are set rigidly in the front of the upper jaw. The "warning" 

 coloration of red, yellow and black rings has been adopted by several non- 

 poisonous snakes, but the latter either have the rings incomplete on the ventral 

 surface or else do not have the red and yellow color adjoining. 



There are several other snakes that possess poison glands but lack the fang 

 development for injecting it eificiently. These, such as Tantilla and Tnmorpho- 

 don, are classed as semi-poisonous snakes. Their grooved, poison-conducting 

 teeth are situated in the back part of the mouth and seldom cause dangerous 

 injury to man. 



Most of us have been thrilled by stories of gigantic boa constrictors or 

 by the "boas" of the circus side show, which are often in reality pythons, 

 larger members of the same family. Two genera of boas are found in the 

 southwestern United States, but they are both small compared with their 

 tropical relatives. Like the pit-vipers, they differ from the other snakes in 

 having vertical pupils and undivided subcaudal plates. The rosy boa is rare 

 and little is known of its habits. The rubber snake is fairly common within 

 its range. Like the larger representatives of the family, it kills its prey by 

 encircling and crushing it. 



Snakes are all carnivorous, most of them eating only the animals they 

 capture and usually refusing to accept anything but live food, even in cap' 

 tivity. Garter snakes, green snakes and little brown snakes live largely on 

 earthworms and insects. Water snakes eat frogs, crayfish and occasional 

 warm-blooded prey. The viperine snakes, (rattlesnakes, copperhead and water 

 moccasin) , colubers, and whip snakes and racers feed mostly on v^arm-blooded 

 animals, chiefly mice. Some snakes may even follow rats or mice into their 

 burrows in order to capture them. All snakes swallow their prey whole, the 

 bones of the jaw being so hinged that the lower jaw drops down and the halves 

 spread apart. An object three or four times the diameter of the snake can be 

 thus engulfed. Once past the neck region powerful muscles crush the food 

 into a more easily manageable mass. Even hen's eggs may be so manipulated 

 and not crushed until they are beyond danger of loss by spilling. 



Contrary to general impressions snakes do not mate for life nor travel 

 always in pairs. Favorable territory frequently supports several snakes of the 

 same species, so that some valiant snake-killer, having destroyed one and being 

 convinced that its mate is near by, can usually find another to support his 



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