36 NORTH AMERICAN BATRAC^HIA AND KKPTILIA. 



33. C. vernalis^ DeKay. Summer Snake. Color above 

 green; below yellowish ; tail between one-third and one-fourth 

 total length ; dorsal rows 15, all smooth; G. 130-140. Eastern 

 and Austroriparian regions. 



34. C. cestiviis, (Linn.) Giinther. Grass Snake. Color 

 above bright green ; below yellowish-white ; tail more than one- 

 third of total length ; dorsal rows 17, the vertebral ones strongly 

 keeled; G. .150-160. Austroriparian region, north to New 

 Jersey and Southern Illinois, 



14. Genus Coluber, Linn. 



Nasals two; loral present; anteorbitals one; postorbitals 

 two; dorsal scales slightly carinate along back, smooth on sides 

 (the carinations sometimes obsolete); anal divided. 



A. Without longitudinal brown bands. 

 a. Scales in 29 rows. 



35. C. e?noryi, (B. and G.) Cope. Vertical longer than 

 head ; color above ashy-gray, with a dorsal series of transverse 

 brown blotches, and two smaller lateral rows (sometimes traces 

 of a third); dorsal blotches narrowly margined with black; 

 beneath yellowish-white, with indistinct brownish blotches; ten 

 or twelve outer rows of dorsal scales smooth, the rest slis^htly 

 carinated; G. 210-220. Mississippi Yalley to Kansas and 

 Illinois. 



36. C lindheimeri^ B. and G. Vertical as broad as long; 

 a series of black dorsal and lateral blotches ; intermediate 

 spaces lighter; scales edged with white; beneath greenish- 

 white; bluish slate color on centers of scutellse, especially pos- 

 teriorly; dorsal scales obsoletely carinated; outer ten rows 

 smooth; G. 225-235. Texas, Arkansas, and Southern Illinois. 



h. Scales in 25 rows ; vertical broader than long. 

 ST. C. vulpinus, B. and G. Fox Snake. Color above 

 light brown, with about 60 transverse,, quadrate, chocolate 

 dorsal blotches, margined with black; one or two lateral rows 

 of same color; dorsal blotches three or four scales long; beneath 

 yellowish-white, with alternating quadrate black blotches; the 

 four lateral rows of scales smooth; G. 200-210. Massachusetts 

 to Kansas, and northward. 



c. Scales in 25-27 rows ; vertical longer than broad. 



38. C. obsoletus, subsp. obsoletus^ (Say.) Cope. Pilot 

 Snake. Color above uniform black; a few scales narrowly 

 edged with white; beneath slaty-black, except 'on the chin and 



