Shell-Bearers 



foreign body. The pearl was esteemed as a jewel so long 

 ago as 300 B.C. By the Romans it was looked upon as a 

 sign of wealth, and seeing that it was found in this country 

 in the time of Julius Caesar, it may have had something 

 to do with the Roman conquest of Britain. 



Pearls may occur in almost any bivalve, and they are by 

 no means confined to the pearl oyster, as is commonly 

 supposed, though in the shell of this mollusc they attain 

 their finest proportions. By the way, the true pearl oyster 

 is not an oyster at all, but is more nearly related to the 

 edible mussel. And what of the pearl? It is simply a 

 perverted growth, as we shall see presently. The Hindoos 

 consider that pearls are consolidated drops of dew. Flashes 

 of lightning have been said to cause them, and that they are 

 nereids' tears is a common belief. That these theories 

 are all very wide of the mark we need hardly state, but 

 the fact remains that, despite the great value of pearls 

 and the amount of attention which has been paid to pearl- 

 fishing, the exact cause of the jewels is still somewhat 

 veiled in mystery. 



That the pearl is the result of a growth in the lining of 

 the shell, over some foreign body that has lodged therein, 

 is well known ; the precise nature of the foreign body is 

 doubtful. Some scientists aver that it is a grain of sand 

 or some similar substance ; others that it is a parasite. 

 Probably the formation of pearls in the various pearl- 

 producing bivalves may be due to different causes. In 

 the Ceylon pearl oyster the cause of pearl formation is 

 certainly a little worm, whose eggs hatch in the sea, but 

 whose larvae enter a bivalve, set up pearl formation and 

 die entombed in a pearl. 



The Ceylon pearl fisheries form one of what may be 

 termed the romantic industries of the world. A fishery 

 which took place at Marichchikkaddi, near the mouth of 

 the Modragain river, has been so graphically described by 

 Dr W. J. Dakin in his excellent little book on pearls that 

 we make no excuse for quoting his words, almost in 



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