OOLtrBEINiE. 3 



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

 body muchi 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. XenelapMs, II. p. 7. 

 Maxillary teeth 22 to 32 ; no suboculars. .., , 



57. Drymobius, 11. p, 8. /^ 



tt Scales disposed obliquely, 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 prsefrontals distinct. 

 t Subcaudals in two rows. 



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



81. Ehadinsea, 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. '^ 



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

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



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

 projecting 91. Cemophora, II. p. 213. 



Maxillary teeth 8 to 12, posterior compressed ; snout more or less 

 projecting 92. Simotes, II. p. 214. 



tt Subcaudals single ; snout strongly projecting ; 

 V maxillary teeth 16 to 19. 



90. Rhinochilus, IL p. 212. r 



tt A single prsefrontal ; 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 prsefrontals ; nasal 

 semidivided, in contact with the prseoeular. 



Eye rather small ; scales as broad as long. j, 



85. Dimades, II. p. 185. 



Eye very small 86. Hydrops, II. p. 186. ^ 



b2 



