COLtTBRIN^. 



* Head distinct from neck ; eye large or rather large ; 

 body much elongate ; scales with apical pits, 

 t Scales forming longitudinal series. 

 Maxillary teeth 12 to 20 .... 54. Zamenis, I. p. 379. 

 Maxillary teeth 25 to 30 ; scales of vertebral row enlarged. 



56. Xenelaphis, II. p. 7. 

 Maxillary teeth 22 to 32 ; do suboculars. 



57. Drymobius, II. p. 8. 



ft Scales disposed obHquely, at least on the anterior 

 part of the body ; maxillary teeth 20 to 25. 

 Lateral scales as long as dorsals. 66. Chlorophis, II. p. 91. 

 Lateral scales much shorter than dorsals. 



70. Thrasops, II. p. 104. 



** Head not or but slightly distinct from neck: eye 

 moderate or small. 



t Internasals, nasals, and praefrontals distinct. 



+ Subcaudals in two rows. 



Maxillary teeth 14 to 24 ; scales without pits : tail conical. 



81. EhadinaBa, II. p. 160. 

 Maxillary teeth 13 to 16 ; scales without pits ; usually one or more 



suboculars; tail long, thick throughout, ending obtusely. 



82. Urotheca, II. p. 180. 

 Maxillary teeth 12 to 20, posterior not compressed; scales with 



apical pits ; no suboculars . . 88. Coronella, II. p. 188. 

 Maxillary teeth 8 to 11, posterior not compressed; snout strongly 



P^°J«^t^"g 91. Cemophora, II. p. 213. 



MaxUlary teeth 8 to 12, posterior compressed .- snout more or less 



P^^J^'^tmg 92. Simotes, II. p. 214. 



tt Subcaudals single ; snout strongly proiecting • 

 maxillary teeth 16 to 19. 



90. Rhinochilus, IL p. 212. 

 tf A single praefrontal ; two internasals. 

 Eye small ; nostril between two nasals. 



83. Trimetopon, II. p. 184. 

 Eye very small ; nasal single. . 84. Hydromorphus, II. p. 185. 



ttt A single internasal; two prasfrontals ; nasal 

 semidivided, in contact with the prseocular. 

 Eye rather small ; scales as broad as long. 



85. Dimades, II. p. 185. 



Eye very small gg. Hydrops, II. p. 186. 



b2 



