THE COMMON INDIAN SNAKES. 807 



these papers, Vol. 22, p. 243). Over and above this, one would 

 expect a greater degree of respiratory embarrassment. Haemor- 

 rhages are not so likely to occur and the local effects according to 

 Lamb are slight. Death, as in other Colubrine toxaemiae, is due to 

 a paralysis of the respiratory centre. 



Treatment. — Fraser and Elliot have shown that Calmette's 

 antivenene has a very feeble action in neutralising the effects of 

 the poison,, so that this agent or the Kasauli preparation may be 

 tried. Otherwise treatment should be symptomatic, and on the 

 lines laid down in my book (Pois. Terr. : Snakes. 1913, p. 145). 



Lethal dose. — The minimal lethal dose for rats was found to be 

 •00009 grammes of dried venom per kilogramme weight of the rodent. 

 In rabbits the dose was "00006 grammes and in cats, the least 

 susceptible of the three animals experimented with, -0002 grammes. 

 Distribution. — Around all our coasts from the Persian Gulf to 

 Tenasserim, the Malayan Region and as far East as New 

 Guinea. At Cannanore though I have no figures to support me 

 I judge that I got at least ten specimens for every one of all other 

 species put together. In Madras in 1917, out of a collection of 199 

 seasnakes, 60 proved to be of this species. Though I have fre- 

 quently witnessed the drawing in of the huge nets (perhaps a mile 

 long) the fishermen use in Ceylon, I very rarely saw any seasnake 

 captured, and never this species. I can find no record of it from 

 the Andaman Islands though very common on the Coast of Burma. 

 Lepidosis. — Rostral. — Rather deeper than broad, projecting below 

 the level of the lip. Nasals. — In contact behind the rostral; the 

 suture from the nostril passes to the 1st labial. Frcefrontals. — 

 Usually touch the 2nd labial (in rare instances the praeoculars 

 meet the nasals). Frontal. — The parietal sutures are equal to the 

 supraoculars or sometimes slightly longer. Supraoculars. — Usually 

 as long and as broad as the frontal. Prceocidar. — One. Postoculars. — 

 One or two. Temporals. — One, large, nearly descending to the lip, 

 often divided into two. Labials. — 7 to 8 ; the first 4 usually entire, 

 the 3rd and 4th touching the eye. Lnfralabials. — 5, the 5th in 

 contact with 3 or 4 scales behind. Marginals. — None. Sublingu- 

 als. — Absent. Two small pairs both widely separated by small scales 

 are regarded by some as such. Gostals. — Two headslengths behind 

 the head 47 to 61, at greatest girth 50 to 70 : imbricate or subirnbri- 

 cate everywhere ; furnished with keels occupying the median ^ to |- 

 of each scale, and frequently twice or thrice denticulated. The 

 keels and their denticulations are most pronounced on the belly, 

 especially in males which may be very rough in consequence. In 

 females and young the keels are less obvious, or even obsolescent, 

 This condition resembles very closely that seen in H. cyanocinctus, 

 and coronatus. Ventrals. — 230 to 361 ; little broader than the last 

 costal rows ; often divided ; laterally keeled as in the last costal rows. 



