POISONOUS SNAKES. 



499 



The Salenoglyph poisonous snakes may always be recog- 

 nized by their broad, flattened heads, and usually short thick 

 bodies. The poison gland of the rattlesnake (Fig. 442, ) is 

 a modified salivary gland. The two fangs are modifications 

 of maxillary teeth, each of which has been, so to speak, 

 pressed flat, with the edges bent towards each other, and 

 soldered together, so as to form a hollow cylinder open at 

 both ends, the poison duct leading into the basul opening. 

 When the fangs strike into the flesh, the muscles closing 

 the jaws press upon the poison gland, forcing the poison 

 into the wound. The poison-fangs are largest in the most 

 deadly species, as 

 the viper ( Vipera), 

 the puff adder 

 (Clotho), the rat- 

 tlesnake, and fer- 

 de-lance (Trigono- 

 cephalns), but are 

 small in the asps 

 or hooded snakes 

 (Naja). The bite 

 of the rattlesnake 

 is intensely painful; 



it is best cured bv Fin. 442. Head of the rattlesnake : an. poison gland 



" and its excretory duct : e, anterior temporal muscle ; /, 



SUCkill " freely lail- posterior temporal muscle ; y, digastricus ; />, external 



" pterygoid muscle ; i, middle temporal muscle ; q, arti- 



cin r , and by Cailter- culo-maxillary ligament which joins the aponeurotic 



. . e . J , capsule of the poison gland ; r, the cervical angular 



IZlllg the WOlincl, muscle ; t, vertebro-mandibular muscle ; u, costo- man- 



-i -i i -i dibular muscle. After Duveruoy. 



and drinking large 



quantities (at least a pint) of whiskey or brandy, sufficient 

 ordinarily to produce insensibility. Deaths from the bite of 

 rattlesnakes are not common, while in India it is estimated 

 that several thousand people annually die from the bite of 

 the cobra 10,000 dying each year from the bite of snakes 

 and the attacks of wild beasts. The "rattle" of the rattle- 

 snake is a horny appendage formed of buttonlike compart- 

 ments ; the sound made by the rattle, which has been com- 

 pared by some to the stridulation of a Carolina locust, or of 

 the Cicada, is an alarm note, warning the intruder ; the rat- 

 tle is sprung before the snake strikes. Allied to this snake 



