244 On the Economical Uses of some species of Testacea. 
six to nine men each, were entered at the custom house of Cancale, 
in France, and carried back one hundred and nineteen millions four 
hundred and seventy three oysters, chiefly to London. On an aver- 
age of 1831—1832, the imports into the same city amounted to 
fifty two thousand and ninety five bushels a year. In or about 1786, 
Glasgow consumed twenty thousand annually, which were carried 
from Leith on horseback or by carts, across the country. ‘The quan- 
tity in the present day must be much greater. In 1803, the con- 
sumption of Paris was estimated at one million dozen, selling on an 
average at six sous per dozen. 
Natural habits—The European oyster is smaller, thinner, and 
more rounded than the Ameérican, while the lower valve is less con- 
cave or vaulted, it is not beaked, and the fish, compared with the size 
of the shell, is smaller and of a different flavor; there are besides, va- 
rious other differences, and their habits are so very dissimilar that there 
can be no doubt at all of their being distinct species. "The European 
oyster is found only adhering to rocks and stones, or occasionally to 
very strong clayey bottoms, and should these be washed away, the 
oyster beds perish. The fish is viviparous, and the young produced 
with a perfectly formed shell. They are, when first emitted, quite 
transparent, and they swim with great quickness, by means of 2 
membrane extending out of the shell. So small are they in this 
state that Van Leeuwenhoek computes that one hundred and twenty 
of them in a row would extend an inch, and consequently a globular 
body, whose diameter is an inch, would, if they were round, be 
equal in size to one million seven hundred and twenty eight thousand 
of them! The vulgar opinion, and that on which the restraining 
laws have been framed is, that the period of spawning is May, at 
which time the young, or spat, is found adhering to the rocks. But 
as the young, as described above, are found in the parents perfectly 
formed and alive in the month of August, this is most probably the 
period of parturition, though it be not till May that they become 
fixed or sufficiently grown to be seen by the common observer. At 
this time they are about the size of a sixpence, and comparatively 
hard and firm, and have been well compared to a drop of candle 
grease in water. In two, or at farthest three years, they are fit for 
the table. The age to which it attains is probably great, but after 
aving, arrived at its full size, the valves are thickened, instead of 
being inereased in length or breadth. From May to July, both the 
male and female oyster are said to be sick, and are in thin and poor 
