MISCELLANEOUS NOTES. 319 



the basin. The rest is then passed through a fine sieve, so that no pearl of 

 even the smallest description shall escape. The only thing that appears to 

 receive no consideration in the matter are the oysters. It is to be hoped that 

 they do not long survive the hot bath ; but on this point the villagers appear 

 to be somewhat doubtful, saying that they have great tenacity of life and 

 do not finally succumb until they have been in the basin some hours. 



Oysters, found on rocks, sand, and on mud, produce very different quan- 

 tities of pearls. I give the following figures for what they are worth — they 

 were given me by men who had worked on all the different bottoms last year, 

 so they ought to be fairly accurate and of some value: "Three thousand 

 oysters found on rocky bottom produce Rl weight of pearls; 6,000 from a 

 sandy bottom and 40,000 from a muddy bottom produce the same weight of 

 pearls." My informants were unable to explain this great difference, and I 

 am unable to offer any reasonable suggestion unless the following may be 

 considered worth anything : — At page 127 of Theobald it is stated that pearls 

 are " merely a deposit of the lustrous lining material of the shell round some 

 foreign and offending object." This view is now apparently disputed, if 

 not exploded. See the following from Dictionary of Economic Products, 

 vol. vi, page 118 ; — 



The popular notion that the foreign matter is generally a grain of sand is untenable. 

 According to several eminent concholo gists, it is in most cases a minute parasite, but Dr. 

 Kelaart believes the nucleus to be in most cases at least an ovum or ova escaped through 

 the distended coats of an overgrown ovary and become imbedded in the interstices of the 

 mantle. " I have repeatedly examined seeds or young pearl," he writes, " in process of for- 

 mation, and with a magnifying power, one-fifth of an inch lens, I was able to see distinctly 

 the outlines of two or three ova through the first or superficial layer of nacre surrounded by 

 groups of ova." Theory is further supported by the fact that pearls are most frequently 

 found imbedded in the mantle " near the hinge (the place where the ovarium is most likely 

 to be liable to rupture) and by the fact that with careEul examination he was generally able 

 to find, when the pearls were not actually found in the interstices of the mantle near that 

 Locality, cicatrices on the structure where they once existed." The difference in the weight- 

 producing capacity of the pearls found on different bottoms would seem to give colour to 

 the popular belief that pearls are nothing more than " foreign and offending objects sur- 

 rounded by the lustrous lining of the shell," but it is quite possible that the real explanation 

 is something quite different. 



The oysters were said, in last year's report, to be found in shallow water. 

 This statement is, I find, only partially true. The oysters found last year 

 were certainly found in shallow water, but I am informed that villagers have 

 often found them in water at various depths — 30 feet or more — so that if 

 this is the case there seems no reason why they should not live in greater 

 depths still. 



I had about 300 oysters opened in my presence, and in each I found 

 always one, sometimes two, small crabs. When only one, it is the ordinary 

 hard-coated grey type found on the sands ; when there is a second it is to 

 all appearance a different kind altogether— a blue shell and very soft. It is 



