( xxxi ) 



Ferania. 

 Scales in 27 rows. Two prsefrontals. 

 Scales in 29 rows. Two small prsefrontals... F. Sieboldii. 



HiPISTES. 



Scales in 39 rows. 

 Colouration of a Hydrophis ... H. hydrinus. 



b. — Scales keeled. 



Cerberus. 



Occiput scaly. 

 A ring of orbital shields ... C. rhynchops. 



HOMALCWSIS. 



Occiput shielded. 

 Brownish olive with dark bars . . . H. buccata. 



Family ACEOCHORDIDiE. 

 Head covered with scales. Nostrils at the top of the snout. 

 Viviparous. 



Chersydrus. 



Scales tubercular in over 100 rows. 

 Colour yellow and gray, banded . . . C. granulatus. 



Family PSAMMOPHID^. 

 Scales smooth. Head distinct. Eye round or vertical. The 

 last maxillary tooth grooved. 



PSAMMOPHIS. 



Scales lanceolate in 15 to 19 rows 



Anal bifid. Prseocular does not reach ver- 

 tical ... P. condanurus. 



Anal entire. Prseocular reaches to the ver- 

 tical ... P. Leithii. 



PSAMMODYNASTES. 



Scales short, rhombic in 17 rows. 

 Head short and thick. Long fangs in 

 front . . . P, pulverulentus. 



