oct.— dec. 1857.] The Pearl Oyster of Ceylon. 



89 



IX. Introductory Report on the Natural History of the 

 Pearl Oyster of Ceylon. By E. F. Kelaart, m. d. 



[This interesting Report is republished from the Ceylon Overland Observer, 

 not only with reference to its intrinsic value, but also to its important bearings 

 upon the Pearl Banks belonging to the Madras Presidency, which have long been 

 in an unsatisfactory state.]— Ed. M. J. 



Having understood that some account of my researches into 

 the Natural History of the Pearl Oysters of Ceylon, is desirable, 

 even at this early period of my labours, I shall endeavour briefly 

 to sketch a Report, that can only be considered in the light of an 

 Introduction to a more extensive and prolonged series of observa- 

 tions ; which, if means are afforded me, may be brought to a more 

 speedy conclusion than I have any prospect of doing at present. 



Before I proceed to detail the results of my researches, since 

 I was commissioned by His Excellency the Governor, in March 

 last, to undertake this desirable investigation, I have to acknow- 

 ledge the great facilities which the aquarium gives, for the inves- 

 tigation of the natural habits of Molluscs, and other moderate- 

 ly sized fresh and sea water animals. Without glass aquaria and 

 a powerful microscope, I should not perhaps have obtained even 

 that information on the minute anatomy and habits of the Pearl 

 Oyster, which is embodied in this Introductory Report. Soon 

 after my appointment, I ordered out large glass aquaria and other 

 apparatus, which will be of service hereafter, to myself, or to those 

 who may be engaged years hence, in reporting to Government, 

 from time to time, the natural condition of the Oysters in their 

 various banks. In the mean time, I have made use of large glass 

 globes and Ceylon manufactured aquaria, made of thick crown 

 glass, Roman cement and slate, purchased from the Naval Store. 

 Large chatties too, and tubs, are also in use. The Oysters thrive 

 best in chatties, but these do not afford the same opportunity of 

 seeing their habits as glass sided aquaria. I have also, in addi- 

 tion to the above named means of observation, had perforated 

 wooden boxes, with a few Oysters in each, deposited in various 



