CHAPTER XL: THE HOG NOSED SNAKES 

 GENUS HETERODON 



Three North American Species that are Interesting from Their 



Peculiar Form and Habits 



THICK-BODIED, pugnacious in aspect and actions, and pro- 

 vided with a peculiar upturned and shovel-like snout, the snakes 

 of this genus may be readily recognised. Their scales are keeled, 

 imparting a dull surface to the body, while the pattern is ar- 

 ranged in rather striking cross-bands or blotches, all of which 

 characters tend to place these creatures in very bad repute in 

 the minds of many popular observers. However, this condition 

 has been intensified by habits these snakes evince of flattening 

 the head and neck to a great degree and hissing loudly. They 

 are the familiar and dreaded puff "adders," flat-headed "adders" 

 or sand " vipers." In spite of their antics, they are quite harmless, 

 and, in fact, their manoeuvres consist largely of bluff for they 

 rarely attempt to bite. 



In the habit of dilating the neck, these snakes resemble the 

 cobras of the Old World and the process is performed in the same 

 manner as with the latter reptiles namely, by means of long 

 ribs that lie close against the backbone when the body is in a 

 passive condition, and spread laterally when the snake is excited 

 or angry. 



With the species of Heterodon, the dentition differs from 

 that of the greater number of the harmless, colubrine snakes. 

 On each side of the back portion of the upper jaw, separated by 

 some space from the other teeth, are two large, fang-like teeth. 

 These are entirely devoid of poisonous properties, however, and 

 are employed by the snake to hold its prey, as the reptile possesses 

 no power of bodily constriction. These snakes feed principally 

 upon toads. 



Three species of the Hog-nosed Snakes these comprising 

 the entire genus Heierodon inhabit North America. They 

 frequent dry, sandy places. An outline of these species is given: 



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