386 
SHELLS. 
[Chap. XL 
sion of my visits to Batticaloa, to investigate the subject 
more narrowly. At subsequent periods I have since re- 
newed my efforts, but without success, to obtain speci- 
mens or observations of the habits of the living mollusca. 
The only species afterwards sent to me were Cerithia; 
but no vigilance sufficed to catch the desired sounds, and 
I still hesitate to accept the dictum of the fishermen, as 
the same mollusc abounds in all the other brackish 
estuaries on the coast; and it would be singular, if 
true, that the phenomenon of its uttering a musical 
note should be confined to a single spot in the lagoon 
of Batticaloa. 1 
Although naturalists have long been familiar with the 
marine testacea of Ceylon, no successful attempt has 
yet been made to form a classified catalogue of the 
species ; and I am indebted to the eminent conchologist, 
Mr. Sylvanus Hanley, for the list which accompanies 
this notice. 
In drawing it up, Mr. Hanley observes that he found it 
a task of more difficulty than would at first be surmised, 
owing to the almost total absence of reliable data from 
which to construct it. Three sources were available : 
collections formed by resident naturalists, the contents 
of the well-known satin-wood boxes prepared at Trin- 
comalie, and the laborious elimination of locality from 
the habitats ascribed to all the known species in the 
multitude of works on conchology in general. 
But, unfortunately, the first resource proved fallacious. 
There is no large collection in this country composed ex- 
clusively of Ceylon shells ; — and as the very few cabinets 
1 The letter which I received from stimulate some other inquirer in 
Dr. Grant on this subject, I have Ceylon to prosecute the investi- 
placed in a note to the present gation which I was unable to carry 
chapter, in the hope that it may out successfully. 
