79 



no large fishes were taken although a large number of small 

 ones, rock-fishes (Serranus chiefly) and spotted soles (Cynog- 

 lossus) were present in most hauls. 



31. Summarizing results the main conclusions I draw are — . 

 (a) That the shallow inshore zone bounded by the 6-fatliom 



line is sufficiently rich in many localities to support a profitable 

 trawling industry conducted by sailing smacks, were it not that 

 such would probably be harmful to more important existing 

 interests ; the principal bottom fish numerous in this zone 

 (during November) are the fine predaceous flat-fish Psettcdes, 

 running to a length of 17 inches, soles (Cynoglossus) of the 

 same size, large rays of the genera Trygon and Aetobatis 

 together with the smaller but more abundant Pieroplaiea micrura, 

 hammerheaded sharks, dogfishes and a variety of small round 

 fishes. Cuttlefish and prawns may also be taken in abundance 

 in the trawl in many places in this zone especially in the 

 neighbourhood of the larger river mouths. 



32. {b) The median shallow water zone bounded respectively 

 by the 6-fathom and the 30-fathom line is quite unfitted for 

 profitable trawling operations. The bottom is uniformly 

 composed of a soft dark grey mud supporting a most meagre 

 invertebrate fauna. The only fish at all plentiful here is 

 Psettodes irumei, but although the majority of hauls on this 

 ground attested its presence, its numbers are too few to make 

 trawling profitable. As an example Of the sparseness of life on 

 this bottom, trawl haul No. 35 at a depth of 22 to 26 fathoms 

 produced only 13 of these fishes, although the trawl was down 

 5J hours ! The remainder of this catch consisted of 12 lbs. of 

 cuttlefish and one pound weight of mixed small round fishes. 



33. (<?) Outside of the 30-fathom line trawling conditions 

 improve greatly, the bottom becomes firmer and is largely 

 composed of fine grey sand,, with more or less admixture of 

 mud, shells and stones. Crabs, squat lobsters (Scyllarus) and 

 fairly large gastropod molluscs abound and large fishes ought 

 to be plentiful. Their existence in quantity has yet to be 

 proved, as the means at our disposal on the Margarita cruise 

 were inadequate. 



A better sea-boat fitted with a suitable trawl-winch and 

 appliances, and operating a larger sized trawl are essential to a 

 definitive test. Personally I am now inclined to think it 

 probable that this zone, which has an average breadth of 25 

 miles and extends the whole way from Cochin to Kundapur, a 

 distance of 260 miles, would prove profitable if worked by a full- 

 powered steam trawler. From what I know of bottom of 

 similar physical character (fine grey sand) elsewhere on the 



