PRELIMINARY DIAGNOSES OF FOUR NEW SEA SNAKES. 341 



I'ale bluifli gif}' above. }rllo\\isli ui' wliitisli bi'low, tlu' youii',' 

 willi iniliBtiia-t dark ilursal bai's nr ccniipli'te baiiild. llrjul gicy. 

 yellowing with age. 



Total leiigtii, 1U25 ; tail 'Jb inin. 



Habitat. Coast of I'erak. Type locality. Kuala Laiiit. Allied 

 to //. 'jrarilix (Sliaw) and //. caidoris Guiitlier. 



Hydrophis consobrinus. 



I'usteriur ina.xillary teetli, 5. ilrad veiy siuall. bod\' very long 

 and slender anteriorly. Kye slightly greater than its distance from 

 the mouth ; rostral broader tlian deep, frontal eipial to or less than its 

 distance to the rostral. One prae- and one or two postoculars. One 

 large anterior temporal, followed by another not so large. or 7 

 iiil)ralabials, third and foui'th touching the eye. Ciiin-shields subecjual, 

 the posterior pair in contact or partly separated b)' a scale. 



2') to 31 scales round the neck, 3G to lo round the thickest 

 jiart ot the body, anteriorly elongate and imbricate, posteriorly hexa- 

 gonal and subimbricate or more or less juxtaposed, with a central 

 tubercle or short keel. V'entrals distinct throughout, 328 to lUl. 



(Jrey above, yellowish white below, with GU to 80 dark gre\' 

 bands or aunuli. Head greyish olive, with a curved yellow mark along 

 the sides of the head and across the snout. 



Total iciigth, lUoT) ; tail 115 mm. 



Ifabitat. t<'ulf of Siani and Coast of I'eiaK-. Type from tiie 

 month ot the Hangpakong river, Siani. 



Allied to 11. fuscialut: (»Schneider) from which it differs in the 

 lower avei'age number of scales round the body, in the lower average 

 number of ventrals. in the size of the frontal, in the small scales 

 behind the parietal shields, and in colouration. 



Hydrophis siameusis. 



Posterior maxillaiy teeth. 8 or ','. Head moderate, body mod- 

 erately elongate : eye eipial to or a lit lie larger than its di>tance from 

 the mouth ; rostral distinctly broader than deep; frontal as long as or 

 shorter than its distance from the rostral ; one i)rae- and one (rarely 

 two) postoculars ; usually a single anterior temporal: 7 or 8 supralabials. 

 third and iViurth ( rarely fifth ) touching the rye. Ciiin-shields .-ub- 

 eipial, the po tmior pair in contact or jiartly separated by a scale. 



VOL. II, i>Ki . l;iir. 



