20 CEYLON PEARL OYSTER REPORT. 



the shelf within the 20-fathom line oft* Negombo was (1) to get a fair sample of the 

 conditions and the fauna for comparison with the pearl bank region off Aripu further 

 north and (2) to explore the ground and the water, as we did wherever possible, for 

 any stages young or old of the pearl oyster. 



There is a record of an old pearl oyster bed, the " Muttu-Parawuttu Paar" lying 

 about 4 miles W. of Negombo in 9 fathoms. No oysters have, however, been found 

 there I believe for many years. We did not find any trace of this paar, but may have 

 been just outside it ; next day however we came upon large quantities of young pearl 

 oysters about 7 miles further to the north. Half-a-dozen hauls of the dredge, two 

 hauls of the 25-foot beam- trawl, with a 7-inch fish-net, and four surface gatherings 

 with the silk tow-net were taken on this first day, off Negombo ; and these, although 

 recorded separately at the time, may now be united as one locality : 



STATION I. Five miles west and south-west of Negombo; 12 to 20 fathoms; 

 bottom coarse yellow sand with a few dead shells; temperature of sea, 77 '5 F. ; 

 dredged and trawled. Amongst the animals were : 



Various sponges ; 



Diphasia mutulata, Lytocarpus (? n. sp.), Campanidaria juncea, and some 

 Plumularian Zoophytes, Caryophyllia sp. and Heteropsammia michelini (with 

 commensal Gephyrea), Gorgonacea (Spongodes, &c.) ; 



Leptoplana sp. and another Turbellarian, and Aspidosiphon corallicola, Filograna sp., 

 Hyalincecia sp., Terebella sp., Acholoe sp. (commensal with Astvopecten), Hesione sp., 

 Ophelia sp. and other Annelids ; 



Crisia sp. and other Polyzoa ; 



Echinus and Temnopleurids (sev. spp.), Salmacis bicolor and S. sulcata, Lovenia 

 elongata, Clypeaster humilis, Echinodiscus auritxis; 



Thyone sacellus, Holothuria atra, H. tenuissima and allied species of "trepang" 

 (up to 16 inches long), Pectinura intermedia and other Ophiuroids, Astvopecten 

 hemprichii, Luidia maculata, Antedon sp. ; 



Lepas sp., Hippolyte sp. (with Bopyrid) and other Macrura, Neptunus sp., Calappa 

 sp., Elxdia sp., and other Brachyura ; 



Acanthochitest penicillatus, Styliola acicula, Teredo sp. (in wood), Area (sev. spp.), 

 Venus lamarcki, Cardium rugosum, Pinna bicolor, Pectunculus sp., Dentalium 

 octagonum, Murex tenuispina and M. haustellum, Oliva Candida, Turbo margari- 

 taeeus, Conus marmot at us, Natica sp., Harpa conoidalis, Umbrella sp., Pleuro- 

 phyllidia sp., Melibe fimbriata and Sepia sp. 



Molgula sp., and some colonies of a snowy white Leptoclinum which grows over the 

 coarse quartz sand and cements the grains together. 



The Tow-net gatherings contained : 



Trichodesmium erythrmim (in quantity), Diatoms, Ceratium tripos and some 

 Foraminifera ; Sagitta sp., Salpa demoeratica-mucronata , and Oikopleura sp. ; 



