262* SNAKES OF CEYEON. 



Tenasserim. Indo -China. The Malay Peninsula, the Anda- 

 mans, Nicobars, and Malay Archipelago to the Philippines, and 

 the Pelew Islands. 



(b) Local : It is an extremely common snake on the Indian 

 littoral, especially on the Burmese coasts. Ferguson says it is 

 a common snake in Colombo, and Haly endorses this remark. 



Genus GERAKDIA. 



(Named in honour of Monsieur Gerard.) 



General Characters. — As detailed for the species. 



Identification. — The costals in 17 rows anteriorly and at 

 midbody, 15 posteriorly, a single internasal, and one supra- 

 labial touching the eye will indicate the genus. 



Habits. — Aquatic, fluviatile, estuarine. 



Food.— Fish. 



Breeding. — Nothing known. 



Poison. — Feebly poisonous, probably quite innocuous to man. 



Lepidosis. — As detailed under the species. 



Dentition. — Maxillary: Diacranterian. Prsecranterian small, 

 anododont, isodont. Cranterian, represented by two pseudo- 

 fangs, grooved on their anterior faces. 



Distribution. — Coasts and estuaries of Peninsular India and 

 Burma. 



Gerardia prevostiana (Eydoux and Gervais). 



(Named in honour of Monsieur Prevost, Superintendent of the 

 Paris Museum when the snake was discovered.) 



Gerard's Water Snake. 



Synonymy. — Coluber prevostianus, Gerarda tricolor, Campy - 

 lodon prevostianum, Heleophis flavescens. 



History. — First referred to and figured by Eydoux and 

 Gervais in 1837. 



General Characters. — A small snake growing to about 2 

 feet. Head moderately depressed, about as broad as the 

 body. Snout moderately long, obtusely rounded terminally, 

 without canthus.. Eye small, inclined upwards ; pupil verti- 

 cally elliptic. Nostrils latero -superior and valvular. Neck 



