REPTILES 219 



E. vulpina (B. & G.)- Fox-snake. Length 1,150 mm.; tail 200 

 mm.; color brown or yellowish, with a series of dark brown blotches 

 which alternate with a lateral series on each side; belly yellow, with 

 dark spots; head often reddish: Ohio to Minnesota; southward to the 

 Missouri; often common, feeding on rats round barns; they often 

 emit a fox-hke odor. 



12. Drymarchon Fitzinger {Spilotes Wagler). Large tropical, 

 non-poisonous snakes with a simple anal plate and smooth scales; 

 upper labials 8; color shining black, above and below: i species. 



Fig. 120. — Pituophis sayi: i, sheath of tongue; 2, epiglottis; 3, glottis {from Cope). 



D. corals coiiperi (Holbrook). Indigo snake; gopher snake. 

 Length 2,300 mm.; tail 330 mm.; scales in 17 rows: GulfStates; north- 

 ward into South Carolina; westward to Texas; one of the largest Amer- 

 ican snakes; often round barns and houses, looking for rats and mice. 



13. Pituophis Holbrook. Bull-snakes. Large, non-poisonous, con- 

 strictor snakes with a long pointed head; scales in 25 to 35 rows; dorsal 

 scales keeled, lateral scales smooth; ventrals about 215; upper labials 

 8 or 9; a peculiar epiglottis-Hke membrane (Fig. 120) in front of the 

 glottis vibrates when the animal is alarmed, producing a loud hiss: 

 4 species, all American; the largest American, harmless snakes; terres- 

 trial and arboreal, feeding on small mammals, birds and eggs, and living 

 usually in dry woods. 



Key to the Species of Pituophis 



ai In the eastern States P. melanoleucus. 



3.2 In the prairie States and Great Plains P. sayi. 



as On the Pacific slope P. catenifer. 



P. melanoleucus (Daudin). Pine snake. Length 1,500 mm.; 

 tail 220 mm.; greatest length 2,400 mm.; color whitish, with a series 



