154 



ECONOMIC ZOOLOGY 



In the Mississippi Valley it may be found as far north as southern 

 Ohio. It is strikingly colored with transverse scarlet and black bands, 

 separated by narrow yellow bands. It is strikingly similar in its colora- 

 tion to the harmless Scarlet King Snake, but in the latter the black 

 bands border the yellow, instead of the yellow bordering the black. 

 It has a small head, with an indistinct neck, and is more or less subter- 

 ranean in habits. Its pupils are round like those of the nonvenomous 

 snakes. 



Just how serious to man is the bite of the Coral Snake it is difficult 

 to say; Ditmars thinks that in spite of its small fangs "It should be 



placed in the list of dangerously 

 poisonous snakes," but its striking 

 coloration and secretive habits cause 

 it to be of little danger to man even 

 within its rather restricted range. 



The Viperine Snakes, or pit vipers 

 include the well-known and widely 

 distributed venomous snakes, the 

 Rattlers, the Copperheads, and the 

 Moccasins. These are all thick- 

 bodied forms, with flat, triangular 

 heads, distinct necks, elliptical (not 

 circular) pupils, and with the highly 

 characteristic "pit" between the eye 

 and the nostril. This pit, Fig. 102, 

 whose function is unknown, is large 



enough in probably all cases to be seen at a greater distance than its 

 owner is able to strike (as a rule a snake can strike only one-half or 

 two-thirds of its length), and may be taken as a sure sign that its 

 possessor is venomous. 



The fangs of these vipers consist of a large, curved, hollow tooth near 

 the front of the upper jaw on either side, Fig. 103. Strange as it may 

 seem, many people call the forked, quivering tongue the fang; what- 

 ever function or functions the tongue may have, it is perfectly harmless. 

 The fangs are surrounded by sheaths of soft tissue, and when the mouth 

 is closed they lie up against the upper jaw, with the needle-like point 

 toward the rear; the sheaths almost hide the fangs, even when they 

 are erected for striking. Each fang is connected with the duct of a 



FIG. 102. Head of rattlesnake, 

 dissected to show the oval poison 

 gland behind and below the eye, and 

 the curved duct connecting gland 

 with fang. "Pit" is between eye 

 and nostril. 



