Of). CONTIA. 



257 



c. Eight upper labials ; veiitrala 133 ; subcaudals 50 ; scales 

 in 17 rows 17. pachi/ura, p. 267. 



2. Nasal divided or semidivided ; scales in 15 rows ; ventrals 

 147-107; subcaudals 29-39. 



Two postoculars 18. miiis, p. 267. 



Three postoculars 19. semiannulata, 



[p. 268. 



II. Rostral large, the portion seen from above as long as or a little 

 shorter than its distance from the frontal : scales in 17 rows. 



Nasal entire or semidivided; ventrals 110- 



137 ; subcaudals 23-40 20. nasus, p. 268. 



Nasal divided ; ventrals 141-160 ; sub- 

 caudals 38-48 21. frontalis, p. 270. 



Table showing Numbers of Scales and Shields. 

 I. Old-World species. 



II. American species. 



Scales. 



(Bstiva 



vernalis 



agassizii ... 



taylori 



episccpa 



torquata 



isozona 



occipitalis ... 

 jiachi/ura ... 



mitis 



semiannulata 



nasus 



frontalis ... 



15 

 15 

 13 

 13 

 15 

 15 

 15 

 15 

 17 

 15 

 15 

 17 

 17 



Ventrals. 



148-1(56 

 119-148 

 128-138 

 126-137 

 145-163 



183 

 158-167 

 147-158 



133 

 147-1(57 



149 

 110-137 

 141-160 



Caudals. 



111-148 

 65-94 

 51-64 

 37-46 

 35-57 



38 

 50-52 

 34-44 



50 

 29-39 



39 

 23-10 

 38-48 



