Chap. IX.] 



SEA-SNAKES. 



311 



they can dive as well as swim. They are often found in 

 groups during calm weather, sleeping on the sea ; but- 

 owing to their extreme caution and shyness, attempts 

 to catch them are rarely successful; on the least alarm, 

 they suddenly expel the air from their lungs and descend 

 below the surface ; a long stream of rising air-bubbles 

 marking the rapid course which they make below. Their 

 poisonous nature has been questioned ; but the presence 

 of a strong perforated tooth and of a venomous gland 

 sufficiently attest their dangerous powers, even if these 

 had not been demonstrated by the effects of their bite. 

 But fortunately for the fishermen, who sometimes find 

 them unexpectedly among the contents of their nets, 

 sea-snakes are unable, like other venomous serpents, 

 to open the jaws widely, and in reality they rarely 

 inflict a wound. Dr. Cantor believes, that they are 

 blinded by the light when removed from their own 

 element; and he adds that they become sluggish and 

 speedily die. 1 



Those found near the coasts of Ceylon are generally 

 small,- — from one to three feet in length, and apparently 

 immature ; and it is certain that the largest specimens 

 taken in the Pacific do not attain to greater length than 

 eight feet. In colour they are generally of a greenish 

 brown, in parts inclining to yellow, with occasionally 

 cross bands of black. The species figured in the accom- 

 panying drawing is the Hydrophis subloevis of Gray; 

 or Hydrus cyanocinctus of Boie. 2 The specimen from 



1 Cabal. Mai. Sept. p. 136. sided, smooth, some divided into 



2 Its technical characteristics are two, by a slight central groove, 

 as follows,— Body rather slender; Occipital shields large, triangular, 

 ground colour yellowish with irre- and produced, with a small central 

 gular black rings. Scales nearly shield behind them ; a series of four 

 smooth; ventral plates broad, six- large temporal shields ; chin-shields 



X 4 



