22 



of Branchiosfoma, sp.^ (Lancelet) were obtained, of which 

 the largest measured two inches in length. MoUusea were 

 also obtained in great variety by passing the debris, which 

 was swept from the floor of the kottoo every day after the 

 oysters had been cleared away, through sieves. The big 

 Murex anguliferus (Elephant Chank) was brought in from 

 the banks by the divers nearly every day, and the animal 

 served up for their hard-earned evening meal. The oysters 

 shells were largely encrusted with bright- coloured sponges, 

 of which the most conspicuous was Clathria indica (n. sp.) 

 an erect-growing bright red species, recorded by Mr. Dendy 

 in his report on my second collection of sponges from the 

 Gulf of Manaar.^ Very abundant, too, was the large cup- 

 shaped Pefrosia testudinaria, of which a specimen in the 

 Madras Museum measures 1*5 feet in height. Enveloping 

 the oyster shells were tangled masses of marine Alcjce,^ and 

 floating in dense masses on the surface was the Sargasso 

 weed, Sargassum vulgare. The various minute living organ- 

 isms entangled in the meshes of the Algse must serve as an 

 efficient food-supply for the oysters. The outer surface of 

 the living oyster shells was frequently covered with delicate 

 Poli/zoa, which also flourished on the internal surface of the 

 dead shells in the form of flat or arborescent colonies. In no 

 single instance did I see an oyster shell from the Tuticorin 

 bank encrusted with coral ; whereas at the Ceylon fishery, 

 on the sole occasion on which I had an opportunity of 

 examining the oysters brought in from the pearl bank, I 

 found the surface of a large number of the shells, both dead 

 and living, covered, and frequently entirely hidden from 

 view by delicate brandling Madrepora or Pocillopora, or the 

 more massive Astrcea, Cceloria, Hydnophora, Galaxea, &c. A 

 specimen of Galaxea encrusting a single valve of an oyster 

 shell, which I picked up on the shore and is now in the 

 Madras Museum, weighed as much as 5 oz. 15 dwts. 



Several species of Echinoderm, which have not hitherto 

 been recorded from the coast of the Madras Presidency,* 



* Specimens of Amphioxus belchcH, Gray, were obtained by Mr. Giles, 

 when dredging from the Marine Survey SS. " Investigator" off Seven Pagodas 

 (Mahibalipuram) 30 miles south of Madras during the season 1887-88. 



2 Ann. 3faff., Nat. Hist., Feb. 1889. 



' The collection of Algfe made at Tuticorin has been sent to the British 

 Museum (Nat. History) for identification. 



* Vide Proc, Zool. Soc, Land., June 19, 1888. 



