o7G LETTER LVIIT. 



young ones, '-as soon as they burst from tlie sand, di- 

 rected by instinct, run immediately towards the sea, 

 which Providence has designed for their abode. Tur- 

 tles have sometimes, although seldom, been caught x 

 on the British shores. 



TESTACEOUS FISHES 



admit of so great a diversity both in the form and co- 

 lour of their shells, that the study of them has been 

 the principal employment of the itves of some natu- 

 ralists; and collections of them have been made at aa 

 expence difficult to estimate, or even to conceive. 



Of the bivalvular kind, the oyster is the most esti- 

 mable, both us excellent and nutritious food, and as a 

 valuable article of commerce. A species of these, 

 called rock oysters, are frequently seen as lar ^ as a 

 plate; and those which are caught on t.he coast of Co- 

 rom'andel, are said to be of so great a size, that one of 

 them will serve several men for a meal ; but they 

 have not so delicate a flavor as those of the smaller 

 kinds. 



All oysters, and many other shell fish, are known 

 sometimes to contain pearls; but thai which particu- 

 larly obtains the name of the peavi oyster, has a 

 large, strong, whitish shell, rough and hard on the 

 outside, 'but smooth and polished within. From this 

 is taken the substance called mother-of-pearl, <;f 

 which so many beautiful trinkets are made. This is- 

 nothing more than the internal coats of the shell, 

 which resemble the pearl in colour and consistence, 

 There are many pearl fisheries in Asia and America; 

 but the principal are those in the Persian Gulf. The 

 pearls there produced are the most beautiful, and 

 consequently fetches the highest prices. 



The pearl fishery is one of the most destructive 

 employments in which any of the human species can 

 be occupied. It is said that*the best divers will con- 

 tinue three quarters of an .hour under water, but many 

 find that fifteen minutes quite exhaust their strength. 

 Every diver descends perfectly naked, except a net 

 fastened to his neck, for the purpose of containing the 

 oysters, and is let down by a rope/ with a stone ct 



