resemble them, that I have always
regretted my inability, on the occasion of my visits to Batticaloa, to
investigate the subject more narrowly. At subsequent periods I have
since renewed my efforts, but without success, to obtain specimens 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]

[Footnote 1: The letter which I received from Dr. Grant on this subject,
I have placed in a note to the present chapter, in the hope that it may
stimulate some other inquirer in Ceylon to prosecute the investigation
which I was unable to carry out successfully.]

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 Trincomalie, 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 exclusively of Ceylon
shells;--and as the very few cabinets rich in the marine treasures of
the island have been filled as much by purchase as by personal exertion,
there is an absence of the requisite confidence that all professing to
be Singhalese have been actually captured in the island and its waters.

The cabinets arranged by the native dealers, though professing to
contain the productions of Ceylon, include shells which have been
obtained from other islands in the Indian seas; and the information
contained in books, probably from these very circumstances, is either
obscure or deceptive. The old writer