30 CEYLON PEARL OYSTER REPORT. 



6 inches long. Even those of 3 inches long showed the ovaries mature. Intestine 

 dark green in colour and contents consisted entirely of a large Navicula-like Diatom ; 



" Arnoglossus" (Psettodus erumei, Bl.) ; 



" Sand-eels" (several small Tccaiolabrus sp. and another) ; 



" Bass" (Scicena maculata, Bl. Schn.) ; 



" Soles" (Cynoglossus spp.) ; 



" Pomfret" or " Pamplette" (Stromateus sinensis, Euphr.) ; 



" Plaice" (Pseudo rhombus arsius) ; 



" Mackerel" (Caranx hippos, Linn., probably = Scomber heberi, Bennett). 



During the day (February 6) several tow-net gatherings were taken. In the 

 morning (8 A.M.) there was a large amount of material, chiefly Alima and other 

 Crustacean larvae, also some large Sagitta, a few Mysids and large Copepoda 

 (Labidocera acuta and Pontella tenuiremis). In the afternoon there were fewer 

 animals, but an enormous amount of Trichodesmium erythrceum, which in places 

 formed a dirty reddish scum on the surface. 



This same locality (Station XVIII.) was also visited later on (March 14th) and 

 trawled over again with much the same results. [Station XIX. is in the northern 

 part of Pal k Bay, and was worked on March 16th see below, p. 83, and map, p. 82.] 



Palk Bay measures about 34 miles from north to south (roughly from off Jaffna to 

 the middle of Manaar Island) and 40 miles from east to west along the south (say 

 from Manaar to Rameswaram), and is 20 miles across further up between Delft 

 Island and Devil's Point. It is about 1 00 miles round the coast from Rameswaram 

 to Punkudutiva, and another 30 across the entrance ; and must contain over 900 

 square miles. Of this area probably two-thirds is trawlable ground, with an even 

 muddy bottom at a depth of 7 fathoms nearly all over, while outside is the still 

 wider area of similar character known as Palk Strait, between Ceylon and the 

 Tanjore Coast. Our hauls in both the north and the south parts of Palk Bay 

 showed that there are plenty of fish, and apparently this shallow area serves as a very 

 valuable " nursery" for young fishes. 



A great part of the Ceylon coast would certainly be very difficult to fish according 

 to European methods, and in some cases it is practically impossible to trawl because 

 of the coral reefs and other obstacles ; but Palk Bay is one of a few areas where 

 there is a considerable extent of ground suitable for trawling, and containing an 

 abundant fish fauna. 



The " Lady Havelock" now steamed round the north end of the island from Palk 

 Bay to Trincomalee. After the Gulf of Manaar 1 regarded Trincomalee as the most 

 important place 1 had to visit and report upon in the first place, because of 

 Dr. Kelaart's experiments and observations in regard to pearl oyster cultivation 

 there some fifty years ago, and secondly, because pearl oysters are known still to 

 live in some parts of the inner bay, where they are collected and eaten by the natives 

 and where pearls are occasionally found. About the time we arrived in Ceylon 



