400 SNAKES OF CEYLON. 



(b) Anomalies — Prefrontals : Sometimes touch the 3rd as 

 well as the 2nd supralabials, rarely completely separated 

 from any supralabials. Supraoculars : Rarely partly divided 

 transversely. 



Dentition. — Detailed under the genus. 



Distribution. — (a) General : From the Mekran Coast to the 

 Chinese sea and North Australia. 



(b) Local : It is apparently a rare snake everywhere. There 

 is one specimen in the British Museum from Mekran (the type 

 of H. guttata, Murray), and Boulenger records another from 

 Karachi Harbour. There is one in the Trivandrum Museum 

 recorded by Ferguson. These appear to be the only examples 

 known from the Malabar Coast of India. It is not represented 

 in the Bombay Natural History Society's collection, and I 

 have failed to procure any specimen from this coast. I found 

 two examples in the Colombo Museum of local origin. There 

 is no record from the Coromandel Coast of India, and it is not 

 represented in the Indian Museum, Calcutta. There are two 

 specimens in the British Museum from Singapore. Gunther 

 throws doubts on its occurrence in the Chinese sea, and I saw 

 no example in any of the Chinese Museums. Practically all 

 the other known specimens are from the Australian Coasts. 

 I have only seen about ten specimens. 



Genus ENHYDRINA. 



(Greek " en " in, " hudor " water.) 



General Characters. — Length up to 4 feet. Habit robust. 

 Body moderately attenuated anteriorly, its diameter about 

 half to two-thirds the extreme depth posteriorly. 



Cranial Osteological Characters. — Nasals : Not sutured to 

 prefrontals or frontal ; confluent posteriorly (a feature unique 

 among hydrophids) ; longer than frontal. Prefrontals : Not 

 meeting parietal, meeting postfrontals. Frontal : As broad 

 as long, meeting postfrontal at rim of orbit. Parietal : 

 Strongly keeled interiorly. Quadrate : Oblique from above 

 backwards, extreme length superiorly half its depth. 

 Maxilla : Extends beyond palatine anteriorly, not extending 

 beyond palatine posteriorly. 



