A MONOGRAPH OF THE SEA-SNAKES (HYDROPHIINM). 



189 



AIPYSURUS. 



Key to the species of Aipysurus. 



(A) Costals in midbody 17 . . . . . . . . eydouxii. 



(B) Ditto 19 . . . . . . . . . . australis. 



(C) Ditto 21 to 25 .. .. .. .. Icevis. 



Aipysurus kydouxii (Gray). 



Tomogaster eydouxii, Gray, Cat., 1849, P- 59- 

 Aipysurus anguillseformis, Giinther, Rept. Brit. Ind., 1864, p. 357. 

 ,, laevis, Jan, Icon. Gen., 1872, livr. 40, pi. ii, fig. 1. 



v, 



Fig. 5. — Aipysurus eydouxii (Icevis). After Jati, Icon. Gen., 1872, livr. 40, pi. ii, fig. 1. 



I have examined six specimens. 



Description. — Rostral, —touches four shields; the portion visible above about 

 half the internasal suture. Prefrontals, -touch no supralabial, usually undivided, 

 but sometimes divided longitudinally on one or both sides into two parts. Frontal, 

 touches six shields, all the sutures sub-equal; one- third to one-fourth longer than the 

 supraoculars, longer than the parietals. Parietal s, entire; sometimes obliquely 

 divided. Nasals, — in contact with the first and second supralabials. Prse ocu- 

 lars. — one. Postoculars,— two. Temporals, —one or two. Supralabials, 

 six, the sixth longest, the fourth only touching the eye (the third also in one specimen 

 on the left side). Inf ralabials, — the fourth is the largest of the series, and touches 

 two scales behind. Marginals, — absent. Sublingual s , — two pairs, the posterior 

 quite separated by a scale. Costals, — smooth; anteriorly 17, midbody 17, poste- 

 riorly 15, (17 in one) the reduction from 17 to 15 takes place close to the site where 

 I count the scales posteriorly and is effected by a fusion of the third and fourth rows 

 above the ventrals. Ventrals, — 138 to 142, three or more times as broad as the 

 last costal row; obtusely keeled in the posterior part of the body. Colour, — yellow 

 or yellowish, with dark brown dorsal bars ending in the flanks, or broken up into 

 ventral spots. 



Habitat. — Indian Ocean, Singapore, Java, Philippines. 



Aipysurus austraus (Sauvage). 



Aipysurus australis, Sauvage in Bull. Soc. Philom., (7), i, 1877, p. 114. 

 ,, fuscus, Giinther , Rept. Brit. Ind., 1864, p. 358. 



(For a figure of this see fig. 6 011 plate vii.) 



