274 BRITISH PEARLS. 



ployed. The greatest depths produce the finest pearls; and 

 a diver will collect from one to four thousand oysters a day. 



HENRIETTA. 



In what part of the shell is the pearl 1 



ESTHER. 



The finest are situated in the fleshy part of the hinge. Pearl 

 appears to be a formation forced upon the animal by some 

 annoying substance in its shell, which it covers with mother- 

 o'-pearl, as the bees invest intrusive wasps or snails with 

 wax, to fix them and prevent them from putrifying. 



HENRIETTA. 



But pearls are sometimes found in England. 



ESTHER. 



Yes; but they are not produced by the same animal, but by 

 the Mya margaritifera. Csesar, on his return from Britain, 

 offered up in the temple of Venus, a corslet of British pearls. 

 The river Conway was celebrated for its pearls, and a large 

 one was taken in this river, and presented by Sir Richard 

 Wynn, the Chamberlain, to Catherine, consort of Charles 

 II, and is said still to adorn the British crown. 



HENRIETTA. 



This is the common oyster (Ostrea edulis]. 



ESTHER. 



Yes it is. Of the purpose to which the oyster shell was 

 applied by the Athenians, I need hardly remind you; but do 

 you know, Henrietta, how to distinguish an old from a young 

 oyster! 



HENRIETTA. 



No. 



Its age is seen by the distance of the circles of laminae of 

 the convex valve, or under shell of the oyster; this lower 



