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NOTES ON A COLLECTION OF SEA SNAKES 



EROM MADRAS. 



BY 



LiEUT.-CoL. V. Wall, c.m.g., c.m.z.s., f.l.s., i.m.s. 



During the months of June and July 1917, 192 sea snakes 

 were collected for me in Madras through the instrumentality of Dr. 

 J. R. Henderson, to whom my thanks are due. It was my inten- 

 tion to make a survey of the Coromandel Coast and to compare 

 results with a similar sj'-nchronous survey on the Malabar Coast. 

 The latter project however failed to crystallise. I selected the 

 months of June and July because past observations had led me to 

 expect the capture of many gravid females, and it will be seen that 

 my expectations were justified. 



As I had to pay a certain price per head, I stipulated that no 

 Enht/drina valakadyn should be included, my previous experiences 

 of marine collecting having shown me, that it might be quite 

 possible to get two or three hundred specimens, and find them all 

 of this species. Fifteen young specimens of this species however 

 did come to bag not being recognised as such. The following 

 remarks on this collection I think worth drawing attention to, in 

 the light of my previous knowledge of sea snakes. 



Although I knew that Enhydris curtus was a very common 

 species I was not prepared to find it even more common than 

 Enhydrina valakadyn. On the Malabar Coast (Cannanore) 1 found 

 the latter verj'- much more abundant. 



After these two species it was my impression that Hyd/rophis 

 cyanocindus cnme a good third in numerical strength and spiralis 

 (vel. briujmansi) a good fourth. It is remarkable th&t cyanocindus 

 proved so uncommon when it is much the most abundant species 

 one meets with on the Sind and Persian Shores, and so common 

 on the Malabar side. Gracilis proved to be very plentiful, far more 

 so than it is on the Malabar side of India judging from my records. 



It is further remarkable that no specimen of caerulescens came to 

 bag though this is quite one of the commonest sea snakes about 

 Bombay. 



Once the monsoon had well set in the sea grew too rough for 

 the fishermen to venture out, so that my captures for the whole of 

 July were far fewer than for the last ten days of June. I give a 

 synopsis of the collection for easy reference, and details of the more 

 interesting specimens under their various headings. 



