2l6 VERTEBRATE ANIMALS OF THE UNITED STATES 



6. Liopeltis Fitzinger. Small, green snakes with smooth scales in 

 15 rows; upper labials 7; ventrals 135: several species in eastern Asia, 



1 in America. 



L. vernalis (Harlan). Green snake; grass snake. Length 400 mm.; 

 tail 130 mm.; color uniform green, lighter underneath: eastern, western 

 and central States; westward to New Mexico; common towards the north; 

 terrestrial, living in the grass and in shrubbery, and feeding on insects. 



7. Opheodrys Fitzinger {Cyclophis Gunther). Small, green snakes 

 with keeled scales in 17 rows; upper labials 7; ventrals 155: several 

 species in Asia, i in America. 



O. CBstivus (L.) Green snake. Length 840 mm. ; tail 320 mm. ; color 

 uniform green; belly yellow: southern New Jersey to the Gulf; westward 

 to New Mexico and northward in the Mississippi Valley to Illinois and 

 Kansas; common; arboreal, feeding on insects. 



8. Salvadora Baird & Girard. Slender ground snakes with a snout 

 surmounted by a triangular rostral shield, giving it a truncated appear- 

 ance in front; scales smooth and in 17 rows; upper labials 8: several 

 species in Mexico, i in the United States. 



S. grahamice B. & G. Patch-nose snake. Length 700 mm.; tail 100 

 mm. ; back with a broad yellow middorsal stripe, bordered on each side 

 by a dark brown stripe of equal width, beneath which is a light brown 

 band; belly yellow ; ventrals about 180: western Texas to California; 

 common, especially in rocky places. 



9. Phyllorhynchus Stejneger, Small slender snakes with a large 

 triangular rostral shield giving the snout a truncated appearance; anal 

 plate single; scales in 19 rows and imperfectly keeled; upper labials 6: 



2 species. 



P. hrowni Stej. Length 325 mm.; tail 42 mm.; color whitish, with 

 15 brown blotches on the back; belly white; scales keeled on the hinder 

 two-thirds of the body and very faintly keeled on the forward third: 

 southern Arizona. 



10. Coluber L. {Zamenis Wagler). Blacksnakes; racers. Large, 

 non- venomous snakes with head distinct from the neck; scales smooth, 

 in 1 5 or 1 7 rows ; upper labials 7 or 8 : many species in the New and Old 

 Worlds, 6 in the United States; active snakes which live on the ground 

 but can also climb bushes and trees, feeding on small mammals, reptiles 

 and frogs; they do not constrict their prey but may kill it by pressing 

 it against the ground. 



Key to the Species of Coluber 



ai Body never striped. 



bi Color black, bluish or olive C. constrictor. 



