74 MADRAS FISHERIES BULLETIN [VOL. XVI, 



generation, 9 to 10 months old. The majority of both ages were, 

 as usual, densely covered with sponge growth (Clathria indica). 

 Dead shells of the younger generation were in quantity in some 

 places. Death in many cases had been recent and the majority of 

 these showed distinct signs of having been bitten, pieces having 

 been snipped out of the ventral margin suggestive of damage by 

 oyster-eating fishes, which were found notably numerous here, 

 seve i Kilati (Batistes mitis) being caught by the No. 4 boat which 

 traversed the greatest extent of rocky bottom, while in the evening 

 after anchoring, several large Vellamln (Lethrinus sp.), noted 

 devourers of shellfish, were taken together with more Kilati. 



Although we found no pearl oysters in quantity, the work 

 of the boats showed that the ground to the east of this group and 

 between it and the Sankuraiya Pattu Par group is excellent chank 

 ground and should be marked as a chank-bed on the chart. It will 

 probably be found to extend also some distance northwards. The 

 chank-bed sand was excellent of its kind — fine grained and very 

 dark in colour, due to the presence of mud and organic particles 

 and so forming an excellent feeding ground to the annelids which 

 constitute the favourite food of the chank. 



Seaweeds were common on these pars, principally Padina and 

 the lamellar olive-brown fucoid so characteristic of the Ceylon 

 Periya Par. 



The characteristic fauna consists of — - 



Spongionella nigra, Suberites inconstans, Clathria indica, Axinella 

 tubulata and Siphonochalina (with the usual commensals) as the 

 most conspicuous and numerous sponges; a coarse form of the 

 decalcifying sponge Cliona, making burrows of large size, is also 

 conspicuous in the blocks of dead corals occasionally met with. 



Eunice tubifex, Trophonia and many small Polynoids and 

 Serpulids, with Gephyreans and Nemertines. 



Dromia sp., Alpheus sp., Gebia sp., Squilla sp. and numerous 

 other small Decapods. 



Pcntaceros lincki was present in quantity with an occasional 

 Linckia miliaris, and numerous Antedon spp. and Ophiuroids. 



No Pinna was taken either on the sand or the rock. 



Ascidians were scanty in number. 



The par is flat-surfaced and in places discontinuous, varying 



from quartzose limestone to compact and extremely hard, brown. 



and purely calcareous rock. The loose fragments numerous in 



certain localities are either of the latter character or are masses of 



