24 CEYLON PEARL OYSTER REPORT. 



or lagoons, that extend up this coast of Ceylon) to Putlani Fort. The tow-net was 

 left out all night, and on being hauled at 5 A.M. was found to contain many large 

 Stomatopod larvas in various Erichthus stages, and some Lucifers, various other larvae 

 as on the previous day and a few Copepods (Labidocera acuta, L. kroyeri, and 

 Calanus vulgaris). Another haul taken at the same spot from 8 to 9.30 a.m. contained 

 a mass of minute plant-life. Navicula and other diatoms, Pediastnim, and many 

 small larvse of worms and Copepod nauplei ; also small adult Copepods (Ectinosoma 

 rosea and E. atlanticuni and Oithona similis). 



A third haul at 11.30 a.m. had swarms of crab zoea and some Foraminifera 

 (Plauorbidina), also the blue Copepoda (Centre-pages violaeeus), Pontella securifer, 

 several species of Labidocera, including a large new species, also a greenish-blue 

 larval Squilla. This last haul was taken further north, over Muttuvaratu Paar, 

 but the difference in these successive gatherings is probably due to some extent to 

 the time of day and to tidal currents carrying streams of plankton past the ship. 



My intention was now to examine the neighbourhood of the celebrated Muttu- 

 varatu Paar lying off the middle of Karativo Island, and perhaps one of the most 

 important of the pearl oyster grounds after the Cheval and Modragam paars. It 

 afforded profitable fisheries in 1889, 1890, and 1891. 



We commenced dredging at 11.30 a.m. and spent the rest of the day in making a 

 traverse from east to west across the paar and into the deep water lying outside 

 it. The first five hauls were all in the neighbourhood of the paar and may be 

 considered as one locality (Station VI.), and several hauls were then taken at two 

 spots (Stations VII. and VIII.) further out, the first at 45 to 50 fathoms and the 

 second at 90 to 100 fathoms. This was one of the localities where we examined the 

 ground outside the known paars, down to the 100-fathom line, with the view of 

 ascertaining whether there was any evidence in support of the statement which had 

 sometimes been made in the past, that there were probably unknown beds of pearl 

 oysters further out and in deeper water from which spat was produced for the supply 

 of the inshore paars. No evidence was found. 



STATION VI. Across Muttuvaratu Paar, 4 to 6 miles west of the centre of 

 Karativo Island ; depth 6 to 9 fathoms ; bottom sand with hard patches of 

 "rock" at intervals; temperature of sea at noon 78 F., at 4 p.m. 79 F. ; 

 specific gravity 1'023. Five hauls of dredge. 

 Spongionella nigra, I'hyllospongia holdsworthi, Axinella doyinaia ; 

 Zoanthns sp. and lilac Actinians, Madrepora cytharea, Montipora sp., Porites sp., 

 Astrseids (two species), Turbinaria cinerascens, Sctrcophytum ehrenbergi, Plexaura 

 indica (with Cirripede galls), and other Alcyonaria ; 

 Sabettaria bicornis and Serpula sp. ; 



Echinaster purpureus, Opliiocnemis marmorata, Cucumaria turbinata ; 

 Pearl oysters, Modiolaria sp., Modiola sp., Doris sp. ; 



