118 REPTILES. 



Rapp, of Tubingen, the author of a celebrated work on the 

 Edentata, who constantly directed my attention to the great 

 variations of colour to which the lower Vertebrata especially are 

 subjected. 



6. Herpetodryas flagelliformis. 



Coach-whip Snake, Anguis flagelliformis, Catesby, Nat. Hist. 

 Carol, ii. t. 54 ; Bartr. Trav. in Carol, p. 219. Coluber flagellum, 

 Shaw, Gen. Zool. hi. p. 475. Herpetodryas psammophis, Schleg. 

 Ess. ii. p. 195 ; Abbildg. t. 44. f. 21-24. Psammophis flagelli- 

 formis, Holbr. N. Amer. Herpet. iv. pi. 2. Masticophis flagelli- 

 formis, Baird fy Girard, Catal. p. 98. Herpetodryas flagelliformis, 

 Dum. Sf Bibr. vii. p. 210. 



Body very slender and elongated ; tail one-fourth the length 

 of body. Scales lanceolate, smooth, in seventeen (nineteen) rows. 

 Above greyish brown, sometimes with darker blotches, beneath 

 lighter, more cr less blotched with purplish brown. 



a. Adult. N. America. Presented by Edward Doubleday, Esq. 



7. Herpetodryas flavigularis. 



Psammophis flavigularis, Hallow. Proc. Ac. Nat. Sc. Philad. 

 1852, p. 178; Sitgreave's Report of an Exped. pi. 11. Masti- 

 cophis flavigularis, Baird $ Girard, Catal. p. 99 ; Marcy, Ex- 

 plor. of the Red River, p. 230. 



Habit slender. Scales smooth, in seventeen or nineteen rows ; 

 two anterior and two posterior oculars; upper ante-ocular reaching 

 the vertical; upper labials eight, the fourth and fifth coming 

 into the orbit. Above dirty yellow, beneath yellowish ; belly with 

 a more or less conspicuous lateral series of darker spots. 



a. Skin of an adult, in spirit. Texas. From Mr. Cuming's 



Collection (seventeen rows). 



Var. On each side of body and tail a yellow, dark-edged band ; 

 a second parallel yellowish line above it. Scales in nineteen rows. 



b. Adult. North America. 



8. Herpetodryas dendrophis. 



Schley. Ess. ii. p. 197, and Abbildg. t. 44. f. 25-28; Dum. $ 

 Bibr. vii. p. 208. 



Scales keeled, in fifteen rows. Olive, with darker cross-bands. 



a. Adult female : discoloured, in fluid. Cayenne. 



