1873.] 39 



On Nepheopsis Stewatitt, a t^ew gentjs at^d species ov mactiuroiTs 

 Crustaceans, dredged in deep water off the eastern coast oi* 

 THE Andaman Islands, — hi/ Jas. Wood-Mason. 



(Road 7th August, 1872, received 16th January, 1873). 

 [With plate IV.] 



In April of last year, I was deputed by the Tinistees of the Indian 

 Museum, with the sanction of the Government of India, to proceed to the 

 Andaman Islands for the purpose of making a collection illustrative of 

 the marine fauna of tliat part of the sea of Bengal in which those islands 

 are situated. I reached Port Blair about the 6th of April, and immediately 

 put myself in communication with the Chief Commissioner, who at once 

 placed at my disposal a well-manned boat and a small steam-launch, with 

 which I dredged for nearly two months with much success from low-water 

 line down to near 50 fathoms. Towards the end of my stay, General Stew- 

 art knowing my intense desire to try my fortune in deeper water, placed at 

 my disposal for one day the S. S. " Undaunted" which had been recently armed 

 and put into commission for service as a guard ship. The time allowed was 

 short, but sufficiently long to enable me to bring away samples of the life 

 supported by the sea-bed at, and beyond, the 100 fathoms' line, and to ascer- 

 tain that the sea-bed was uniformly covered with a thick deposit of fine 

 olive-coloured mud derived from the waste of the coral-reefs and of the 

 sandstone and serpenti:ie rocks of the islands.* This mud was not 

 very productive, yielding only a few annelids, but was crowded with dead 

 shells of Pteropods and Dentalmm and with fragments of a large Bra- 

 chiopod. 



It was in the last cast of the dredge that I had the good fortune to 

 capture the interesting addition to the crustacean fauna of these seas, de- 

 scribed in the following pages. It is closely allied to Neplirops Norvegicus 

 of northern European seas, so closely allied, indeed, that were it not for the 

 absence of the squamiform appendage of the antennae, I should be under the 

 necessity of placing it in the same genus as a second species. The absence 

 of this appendage, however, leaves me no choice but to establish a new genus 

 for its reception. 



* The following rough analysis by Mr, Tween, the chemist of the Geological Sur- 

 vey of India, will show the proportion of insoluble matter : 



Soluble in H CI mostly Ca Cog, 42-8 



Insoluble clay and sand, 572 



loo-o 



