36 CEYLON PEAEL OYSTER REPORT. 



Polynoe sp., Ghjcera decipiens ; 

 Strombus sp. and other common Molluscs ; 

 Amphioxus (ajjparently undetermined). 



STATION XXVIII. Middle, of China Bay; depth 7 to 14 fathoms; bottom black 

 sandy mud ; several hauls of dredge. 

 Holothuria gallensis, n. sp. (Pearson), Astropecten hemprichii, A. polyaoanthus ; 

 Ghjcera (small pink), and some long calcareous worm tubes, &c. 



STATION XXIX. French Pass ; depth 4 to 7 fathoms ; bottom mud with a few 

 stones ; several hauls of dredge. 

 Holothuria marmorata (the large yellow, spotted brown trepang) ; 

 Some Molluscs, Annelids and Polyzoa (including Adeonct sp.). 



STATION XXX. Nicholson's Cove; depth 4|~10 fathoms; bottom muddy sand; 

 dredged. 



Euspongia officinalis ; and a Cubomedusa ; 



Holothuria atra (the large black and pink trepang) ; 



Hyalincecia sp. ; 



Strombus succinctus, S. sibbaldii, and a few other common Molluscs. 



The shoal at the inner end of Nicholson's Cove has a hard bottom with occasional 

 boulders, which are covered with small rock oysters up to 3j inches long (average 

 size 2 inches). It is one of the few spots at Trincomalee which would probably do 

 well for the pearl oyster. 



Mr. Hornell and I managed to land also during this day at various points to 

 examine the shore and the shallow-water fauna which was very important here 

 because of the remarkable fact that the pearl oyster is found living naturally between 

 tide-marks. 



At the far end of Nicholson's Cove we found one or two dead sjjecimens of the 

 commercial sponge, and we also dredged a piece which proved to be Euspongia 

 officinalis. This showed that it evidently grows in the neighbourhood, and we have 

 since found it in quantity. In the mangrove swamps which fringe the ends of this 

 and some other coves there are great numbers of small land crabs (Ocypoda 

 macrocera) and also of the semi-terrestrial fish Periophthahnus, some of which we 

 caught, with some difficulty. We tried to keep the Periophthahnus alive in our 

 tanks on the ship, but the little fish persisted in coining out of the water and getting 

 on deck. They scrambled up the vertical wooden sides by taking advantage of the 

 angles at the corners of the tanks. 



We waded over all the shallower parts of the harbour where Dr. Kelaart 

 had investigated the pearl oysters in 1857, and where Mr. Colomb reported 

 that oysters are now found by the natives. The chief place is between Powder 

 Island and the shore near the wharf (fig. 2). Here the bottom is hard gravel with 



