172 ON THE NATURAL HISTORY OP 



these extensive beds of young oysters bad existed, the numerous native 

 divers employed could not have failed to have seen them. These beds 

 were first observed by Mr. Vane, and Capt. Duncan, of the colonial steamer 

 " Pearl," in Oct., 1858, when none of the young oysters (judging from the 

 shells Mr. Vane sent to me for examination) could have been more than 

 six or seven months old ; most of them under six months. 



The observations made on the shells of the fisheries of 1857, 1858, and 

 1859, lead me to infer that the fishery of 1857 was premature. The same 

 series of observations led me to conclude that the last fishery of the Cheval 

 Paar oysters, in March, 1859, was the latest safe period that oysters could 

 have been left unfished in this bank, and that these oysters could not 

 have been less than seven years old. The general appearance of the shells, 

 their weight, and the characters of the internal soft parts of the oyster, 

 showed very distinctly to one who has carefully observed the oysters fished 

 in 1858, that the oysters of 1859 were older, and near the termination of 

 their life. These external and internal characters will serve for guidance 

 hereafter to all employed in the pearl fisheries of Ceylon, and will be faith- 

 fully detailed in my final report, or treatise, on the natural history of the 

 pearl oyster. In the meantime, I can assure those sceptical of the possi- 

 bility of the zoologist determining the age of the oyster, as the veterinary 

 surgeon does the age of the horse, by looking into its mouth, that the age 

 of the pearl oyster can only be determined satisfactorily by looking into the 

 contents of its two valves, and remarking the characters of the internal 

 parts, and their relative position in diiferent periods of their life. I am 

 only waiting for some more information on this head, before full particulars 

 are laid before Government. In such an important matter, a zoologist 

 cannot be too cautious in giving an opinion, which, if found hereafter to be 

 erroneous, may not only affect his reputation, but likewise make the Ceylon 

 Government a pecuniary loser. It is my object and wish to give, at the 

 conclusion of my labours, such rules for the guidance of future inspectors 

 of pearl banks (who, I hope, will be intelligent persons, with even a little 

 taste for natural history), that the pearl banks of Ceylon will have, in 

 future, less chance of being prematurely or over-fished. 



From information conveyed to me by Mr. Worsley (the late inspector), 

 and the English divers employed under him, I find that I was quite correct 

 in stating, in my former reports, that the rude and rough process of native 

 diving caused the destruction of the old oysters. No old oyster was found 

 in that part of the Cheval Paar Bank fished in 1857 and 1858, and, as there 

 were many oysters left there at the end of those fisheries (though not in 

 aggregate masses), it is natural to infer that, had they not been disturbed, 

 some of them would have lived as long as oysters brought up this year 

 from unfished portions of the same Paar, which, doubtless, were of the 

 same ages. It follows, therefore, that my proposal to leave portions of 

 banks unfished, for breeding purposes, is a justifiable one, and of great 

 practical importance. From the prevalence of cholera, the fishery of 1858 

 was abruptly stopped, consequently large masses of oysters were left un- 



