2 OOLtrBBIDiE. 



Maxillary teeth 6 to 9 ; scales without pits ; snout cuneiform, pro- 

 jecting 55. Lytorhynchus, I. p. 414. 



Maxillary teeth 12 to 16 ; scales with apical pits. 



89. Hypsiglena, II. p. 208. 



2. Palatine and pterygoid bones toothed; pupil round; an- 

 terior mandibular teeth much larger than the posterior ; 

 scales with apical pits. 



a. Internasal shield entering the nostril; maxiUary teeth 

 12 to 14 52. Pseudaspis, I. p. 373. 



6. Internasal nat entering the nostril, 



u. Lateral scales disposed obliqaely, at least on the 

 anterior part of the body ; eyes large. 



Maxillary teeth 15 to 20, the posterior slightly enlarged ; scales in ^ 

 21 to 25 rows 58. Phrynonax, II. p. 18. X 



Maxillary teeth 20 to 82, the posterior strongly enlarged ; scales in 

 13 or 15 rows 71. Leptophis, II. p. 105. ^ 



/3. Scales forming longitudinal series ; maxiQary teeth 11 

 to 20. 



Posterior maxiUary teeth strongly enlarged and separated from the 

 rest by an interspace ; scales narrow, lanceolate. 



72. Uromacer, II. p. 115. 

 Posterior maxiUary teeth slightly enlarged. 



73. Hypsirhynclms, II. p. 117. 



Posterior maxiUary teeth strongly enlarged and separated from the 

 rest by an interspace ; scales moderately elongate. 



74. Dromicus, 11. p. 118. ^' 



X 3. Palatine and pterygoid bones toothed ; pupil round ; man- 

 dibular teeth subequal, or anterior a little enlarged. 



a. Longitudinal series of scales in even numbers ; maxiUary 

 teeth 20 to 33. 



Scales forming longitudinal series. 



53. Zaocys, I. p. 374. 

 Lateral scales oblique 63. Herpetodryas, II. p. 71. X 



6. Longitudinal series of scales in odd numbers; ventrals 

 rounded or obtusely angulate lateraUy ; subcaudals not 

 angulate lateraUy. 



a. Maxillary teeth forming a continuous series, or the 

 last two or three separated from the rest by a very 

 short interspace. 



