ii 



iCey to the Indo-Australian species. 



y4. Ventrals broader than the surrounding shields. 

 I. Diameter of the eye about half its distance from 



the nostril; scales in 19 or 21 rows l. C. rit/its p. 36. 



II. Diameter of the eye one third to one fourth its 

 distance from the nostril. 

 17. Interocular width equal to the length of the 



snout; scales in 21 rows 2. C. Uncatus p. 37. 



b. Interocular width more than the length of 



the snout; scales in 23 rows 3- C. opisthorhodtts p. 38. 



B. No enlarged ventrals. 



1. Nasals forming a suture behind the rostral; 



scales in 20 rows 4. C houkngeri p. 38. 



2. Nasals separated from one another; scales in 



22 rows 5. C. isoleph p. 38. 



I. Cylindrophis rufus (Laur.). 



Anguis rufa.^ Laurenti, Syn. Rept. 1768, p. 71. 



Cylindrophis riifus.^ Boulenger, Cat. Sn. I 1893, p. 135 (s. syn.). 



Diameter of the eye about half its distance from the nostril ; 

 the distance between the eyes more than the length of the 

 snout ; nasals forming a suture ; frontal at least as large as the 



Fig. 19. Cylindrophis rufus (Laur.) X Vj- I-ower view of head. X */;i- 



supraocular, larger than the parietals, as long as its distance 

 from the rostral or longer ; six upper labials, third and fourth 

 entering the eye. Scales in 19 or 21 rows; ventrals not twice 

 as large as the neighbouring scales, 185 — 245; anal divided; 

 subcaudals 5 — 10. 



