PRESERVING AND SKINNING FISHES. 
making an incision under tlie belly, a little on one side, so as 
to avoid cutting the fins ; then, raising the skin from the sides 
by the handle of the scalpel, separate the body from the tail, 
and turn the skin towards the back in order to save the 
dorsal fin, detaching the body from the head near the occiput, 
and withdrawing the gills in order to wash and dry them. 
The skin is now ready either for stuffing, sewing up, and 
mounting, or for stretching between sheets of paper, which 
preserves its colours ; in this process the fins are afterwards 
fixed upon plates of cork or cartridge-paper by means of pins. 
There is not much to commend in this last process, for the 
fins, which are the most striking characteristics of the fish, 
soon become defaced. 
Preserving Crustacea. — Small Crustacea are easily pre- 
served by plunging them into spirits, or even into chalky 
water, in which they may be preserved some time ; after which 
they may be taken out and dried. Marine salt also preserves 
them ; but for larger species other means must be employed, 
which approach to the skinning process although not quite 
belonging to it. In order to get rid of the fleshy matter and 
the gills, it is necessary to raise the shell which covers the 
back of most of the species. The carapace, as the shell upon the 
back is called, is replaced, after covering the bed with arsenical 
soap and stuffing with cotton to replace the flesh removed. 
The shell is held in its place by being gummed round the 
edges. When operating on species furnished with formidable 
claws, the smaller opposing claw may be removed, the flesh ex- 
tracted through the orifice, and the claw restored to its place. 
Mollusks, as the occupants of these shells are called, are some- 
times covered by a shell, in other species the body is always 
naked. Both the marine, fluvial, and terrestrial species, may 
be preserved in alcohol. The shelless mollusk may be other- 
wise preserved alive; but those with the shell, where it is desired 
to preserve that appendage apart from the animal, the only 
mode is to plunge it into some spirit in which it can only live 
a few minutes ; when dead, it is easily withdrawn from its shell 
by means of a piece of wire. When it is wished to preserve 
the shell and bring out its fine colours, a weak solution of nitric 
acid is employed, brushing it with a hard brush ; for a second 
washing use pure water. After which it is again plunged 
into fresh water to remove any of the acid which may remain, 
when it may be wiped dry with a soft rag, and a coating of 
oil applied which brings up its colours. 
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