370 



SHELLS. 



[Chap. XI. 



sunrise to fish, and at evening return to their solitary 

 breeding-places remote from the beach. The strand is 

 literally covered with beautiful shells in rich profusion, 

 and the dealers from Trincomalie know the proper season 

 to visit the bay for each particular description. The en- 

 tire coast, however, as far north as the Elephant Pass, is 

 indented by little rocky inlets, where shells of endless 

 variety may be collected in great abundance. 1 Dur- 

 ing the north-east monsoon a formidable surf bursts 

 upon the shore, which is here piled high with mounds 

 of yellow sand; and the remains of shells upon the 

 water mark show how rich the 

 sea is in mollusca. Amongst them 

 are prodigious numbers of the 

 ubiquitous violet-coloured Ian- 

 thina 2 , which rises when the 

 ocean is calm, and by means of 

 its inflated vesicles floats lightly on the surface. 



The trade in shells is one of extreme antiquity 

 in Ceylon. The Grulf of Manaar has been fished from 

 the earliest times for the large chank shell, Turbinella 



1 In one of these beautiful little 

 bays near Catchavelly, between 

 Trincomalie and Batticaloa, I found 

 the sand within the wash of the 

 sea literally covered with mollusca 

 and shells, and amongst others a 

 species of Bullia (B. vittata, I 

 think), the inhabitant of which 

 has the faculty of mooring itself 

 firmly by sending down its mem- 

 branous foot into the wet sand, 

 where, imbibing the water, this 

 organ expands horizontally into a 

 broad fleshy disc, by which the 

 animal anchors itself, and thus 

 secured, collects its food in the 



ripple of the waves. On the 

 slightest alarm, the water is dis- 

 charged, the disc collapses into its 

 original dimensions, and the shell 

 and its inhabitant disappear to- 

 gether beneath the sand. 



BULLIA VITTATA., 



2 Ianthina communis, Krauss, 

 and I. prolong at a, Blainv. 



