es — 
4 
On the Economical Uses of some species of Testacea. 245 
condition, but by the end of August they have again recovered, are 
fat and in season. The sexes are distinguished by the fishermen, 
by the color of the fringe, that of the male being black, or dark col- 
ored, that of the female white. Sand is prejudicial to them, a mix- 
ture of fresh water advantageous. The shell, according to Mr. 
Hatchett, is farmed of carbonate of lime and a great proportion of 
animal gluten, but more intimately mixed, and not lying in regular 
layers, as in the perlaceous shells.* The oyster frequently contains 
shining intestinal worms, or animalcules, which may be seen by 
opening the shell in the dark. A most destructive animal in an oys- 
ter bed is the sea-star, (Asterias glacialis, Linn.) which clasps its 
rays round the shell and perseveres till it has sucked out the inhabit- 
ant. Another enemy is said to be the muscle, (Mytilus edulis, 
Linn.). 
Fishery.—in both England and France the season for fishing for 
the oyster is restricted by Jaw. In the former country the time al- 
lowed for collecting the spawn from the sea is May, when the dredg- 
ers may take all they can procure, but after that month they are 
liable to be convicted of felony if they disturb it, and are only allowed 
to take such oysters as are the size of half a dollar. The spawn, 
Or spat, as it is technically called, is dredged up, and if not too small, 
they separate it from the shells and stones to which it is adhering, 
and these they are obliged again to throw into the water to prevent 
the beds being destroyed. The spat is thrown into creeks or into 
shallow water on the shores, to increase in size and fatten, and in 
such situations is considered private property. At Preston Pans the 
Cras se eee ee Ree ts Signs 
* Professor Rogers doubts the accu f tk 
matter conininedt in this shel, ool he supposes that there only ¢ exists a 
very minute portion of gluten. In this opinion he states that he is supported by 
the experiments of Bucholtz and Brandes, and those he himself made on the Os- 
trea Virginica, What the shells were which were used by the former gentleman, 
which instead of proving Mr. Hatchett’s experiments to be in the main incorrect, 
only tends to prove that the species are perfectly distinct, and not mere varieties. 
The quantity of gluten contained in the Ostrea edulis, is well known to even the 
most superficial observer, where the shell is common, and may be found in the 
large and thick specimens, or on the decaying of the shell, between the inner and 
lamine, frequently in great quantities. It is of a dirty yellow color, and 
thick and clammy in its consistency. See Silliman’ s Am. Jour., Vol. xxvr. p. 361. 
