The Hog-nosed Snakes 



a. Central portion of abdomen yellow or greenish. 



Ground-colour yellow, brown, reddish or olive, with 

 large, dark blotches on back and smaller ones on sides. 

 Sometimes entirely black. Pattern rather irregular. 



COMMON HOG-NOSED SNAKE, H. puityrbinus. 

 Distribution. Massachusetts to Florida; westward 



to the Missouri. 



Gray or brown, with large blotches on back and smaller 

 ones on sides. The pattern is fairly regular. Smaller 

 than preceding species, with sharper snout. 



SOUTHERN HOG-NOSED SNAKE, H, simUS. 



Distribution. Florida and Georgia to the Mississippi. 



b. Central portion of abdomen, black. 



Yellowish; large blotches on back and two rows of smaller 

 ones on sides. Snout very sharply upturned. 



WESTERN HOG-NOSED SNAKE, H. nasicUS. 



Distribution. United States west of the Mississippi; 

 northern Mexico. 



Detailed descriptions of these species follow: 



THE COMMON HOG-NOSED SNAKE* 

 Heterodon platyrhinus, (Latreille) 



The largest species attaining a length of over a yard. With 

 its very thick body, triangular, flat head and turned-up nose, it 

 looks highly formidable. 



Colouration. The body-colour may be yellow, brown or 

 reddish, with an irregular pattern, consisting of large patches 

 of dark brown or black upon the back from the neck to the base 

 of the tail, where they assume the formation of half-rings. These 

 blotches are separated by interspaces of ground-colour that show 

 a more intensified hue than upon the sides. In alternation with 

 the blotches on the back is a row of smaller blotches on each 

 side. The edges of the abdominal plates are generally blotched 

 or profusely spotted with black. The central portion of the 

 abdomen is yellowish or greenish. 



Variations. The variability of shades in the ground-colour 

 of different individuals and the arrangement and size of the 

 blotches are great. Many specimens have a tinge of bright 

 brick-red upon the neck, while the remainder of the body is 

 marked in ordinary fashion. At the time of compiling this de- 



* Also known as Spreading Adder, Puff Adder, Flat-headed Adder, 

 Blow Snake and Sand Viper. 



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