SNAKES OF CEYLON. 415 



Costals : As broad or broader than long ; square, oblong, 

 or hexagonal ; juxtaposed everywhere, with a central tubercle 

 Last three or four rows enlarged, with the tubercles in old males 

 developed into prominent spines. Two heads-lengths behind 

 the head 29 to 36 ; at midbody 30 to 45 ; two heads-lengths 

 before the vent 30 to 42. Ventrals : 151 to 219 ; entire, and 

 slightly broader than the last costals anteriorly ; divided 

 posteriorly for a variable length, each half with a central 

 tubercle, or in old males spines. Anal : Divided into four 

 or six. 



(b) Anomalies — Rostral : Sometimes partly divided in the 

 median line above. Nasals : The suture from the nostril very 

 rarely passes to the 1st supralabial. Prefrontals : Very rarely 

 fail to meet the 2nd supralabial ; very rarely touch the 3rd 

 as well as the 2nd. Frontal : Rarely partly disintegrate 

 posteriorly. Parietals : Very rarely not broken up ; some- 

 times broken up into more than three parts. Postoculars : 

 Rarely two. Supralabials : The 3rd sometimes divided, 

 forming the so-called loreal of some authors. The 3rd as well 

 as the 1st and 2nd very rarely touch the nasals. Sometimes 

 the 3rd, 4th, and 5th, or the 4th only, touch the eye. Infra- 

 labials : Rarely the cuneate scales fail to meet, and so allow 

 the 3rd, or 3rd and 4th, to partly reach the border of the lip. 



Dentition. — From three skulls in my collection. Maxillary ; 

 Postnodal, 3 or 4. Palatine : 5 to 6. Pterygoid : 18 to 22. 

 Mandibular : 12 to 16. 



Distribution. — (a) General : From the Persian Gulf to the 

 Malay Archipelago. 



(b) Local : I have found it very common on the Malabar 

 Coast (Cannanore) and Coromandel Coast (Madras). One 

 collection of 192 hydrophids from Madras furnished 84 

 examples of Shaw's seasnake. There were three specimens 

 in the Colombo Museum when I examined the collection, and 

 others from the Ceylon coast are preserved in the British 

 Museum. It appears to be rare on the Burmese side of the 

 Bay of Bengal, for out of many seasnakes collected for me 

 I have had no specimen. The Indian Museum had one 



