114 



favoura"ble for their nourisliinent and growth, many of them 

 survive to become the source of considerable revenue." How 

 great is tbo struggle of the pearl-oyster for existence is very 

 clearly shown by the records of the Tuticorin inspections, in 

 which, time after time, a bank is noted in one year as being 

 thickly covered with young oj'sters, and in the next year as 

 being blank. Not, in fact, till a bank is thickly covered with 

 oysters two years' old can any hope be held out that it will 

 eventually yield a fishery. 



Outside the west Cheval Par a sand flat extends for some 

 distance north and south, from which the dredge brought 

 up masses of coarse, broken shells, and, a,mong other speci- 

 mens, large numbers of Aniphioxus and Cli/pemter humiliHj 

 and single specimens of Ophiothrix aspidota and Astropecten 

 hempricliii ; the digestive cavity of the latter being distended 

 by a large Mevetrix (M. casfcuifa) and seven other smaller 

 molluscs, which it had swallowed. From the stretch of sand 

 between the east and west Cheval Pars the Echinoids Eclimo- 

 discus auritwi and Metalia stemalis were obtained. 



During our stay on the west Cheval Par, large numbers 

 of the butterfly Popilio {Mcnelaides) hector were seen daily 

 fluttering around the ship 10 miles out at sea. The Active 

 steaming at the rate of 4 knots an hour, and the diving 

 boats under sail caught many seir fish {Ci/bucm guttattim) 

 with a long line towing astern and made fast to the yard- 

 arm of the lug sail, and baited with a piece of white rag. 

 For catching seir the hooks are, sometimes, baited with a 

 small fish or the white of a cocoanut cut into the shape of 

 a fish. From the barque at anchor many Balistes and the 

 crimson-coloured Lutianus erythropterus were caught by the 

 crew with lines baited with fish. The stomachs of the former 

 always contained crushed pearl-oysters, and those of the latter 

 small fishes. 



On the 1-lth we inspected the small Periya Par, situated 

 3 miles westward of the west Cheval Par, which we 

 found irregularly stocked with young oysters. Sounding 

 seaward from the bank, we found 9 fathoms at a distance of 

 1 mile, 14 fathoms at a distance of 2 miles, and did not 

 strike bottom at 150 fathoms at a distance of 4 miles. The 

 sea bottom shelves here less abruptly than outside the 

 Muttuwartu Par, where a depth of 150 fathoms was obtained 

 at a distance of | of a mile from the seaward face of the 

 bank. The thermometer registered 54" at 150 fathoms, and 

 59° at 100 fathoms, the surface temperature being 83°. On 



