426 SNAKES OF CEYLON. 



Costals : Broader than long, hexagonal, and juxtaposed 

 everywhere. Each scale has figure -of -8 tubercles centrally 

 on the Ventral aspect ; a single central tubercle at about 

 midcosta, but dorsally these may be absent. They are most 

 pronounced in males, and obsolescent in females and young. 

 Two heads -lengths behind the head they number 40 to 54, 

 41 to 61 at midbody, and 41 to 61 two heads -lengths before 

 the vent . The rows are more numerous in females . Ventrals : 

 284 to 339 ; not well developed, being little, if at all, larger 

 than the adjacent costals ; bituberculate laterally. Anal : 

 Divided into four parts. 



(b) Anomalies — Nasals : When an outer suture is present 

 it passes from the nostril to the 2nd supralabial. Prefrontals : 

 Sometimes do not meet the 2nd supralabial, owing to the 

 contact of the nasal with the prseocular. Supralabials : 

 Except the first two or three all are subject to division, forming 

 the so-called loreals, lower prseoculars, and suboculars of some 

 authors. Sublinguals : One or two pairs of slightly enlarged 

 scales, both always widely separated may be taken as such 

 in many specimens. 



Dentition. — Detailed under the genus. 



Distribution. — (a) General: Persian Gulf to Tenasserim 

 and the Andamans. Beyond Indian limits it has a Very 

 wide range, extending to Japan, Australia, New Zealand, 

 South Africa, and the western coast of North America. 



(b) Local : It is moderately abundant around the Indian 

 Coasts. Ferguson, speaking of Ceylon, remarks t^hat it is 

 common about Colombo and the pearl fisheries. Varieties 

 A, D, and E have been met with around the Ceylon Coasts. 



Genus LATICAUDA.* 

 (Latin " latus " flat, " cauda " tail.) 

 General Characters.— Head relatively broad. Nostrils 

 lateral, pierced in an elongate entire nasal shield. Length 

 moderate. Habit robust. Body of even calibre and cylin- 

 drical throughout. Tail highly compressed. 



* As pointed out by Stejneger (Herp., Japan, 1907, p. 402) Laurenti's 

 Laticauda, dating from 1768, has a prior claim to Latreille's Platurus, 

 which dates from 1802. 



