188 
SALMON. 
columns, cranial and other bones, with the denser tissues, as 
the lens, etc. The number of hones in several cases shewed 
that these fishes had enjoyed a most ample repast, since they 
belonged to species from eight to ten inches in length. Some 
pieces of cartilage, skin, and pigment cells seemed to belong 
to Smelts, but most of the vertebr® belonged to larger fishes. 
The other kinds of food found in the stomach consisted of 
fragments of small fresh-water Crustacea, with a portion of a 
Shrimp in one or two of these fishes; and an occasional piece 
of insect cuticle. Accompanying a quantity of mucus, which is 
found in the intestines, is a number of white or yellowish masses, 
which are gritty, and consist of calcareous crystals; of which 
the origin is an interesting question, but it is not influenced 
by the kind of food. The skeleton of the Salmon being of 
small specific gravity, and deficient in earthy matter, it may be 
that the excessive elimination of salts keeps down the specific 
gravity; or the circulating fluid by this means may so adapt 
the hones to the varying density of the salt and fresh water, 
that their specific gravity is in accordance with the medium in 
which they swim. The rapidity and power of digestion in this 
fish are extraordinary; and the true state of the matter seems 
to be, that the Salmon when in fresh water feeds rarely and at 
intervals, but not from want of voracity. There is abundance 
of parasitic animals in the entrails of this fish. I was informed 
by Mr. Bewick, the eminent engraver on wood, that when a 
gentleman of Newcastle had lost a gold ring from a boat on 
the Tyne, he was so fortunate as to recover it from the stomach 
of a Salmon which was purchased in the market at Newcastle. 
But whatever be its food, it is noticed that this fish soon declines 
in growth and the quality of its flesh in fresh water; but it is 
then successfully fished tor with large artificial flies, which must 
be of gorgeous and glaring colours; and these beyond doubt 
are viewed by the fish as native inhabitants of the stream rather 
than of the air, as is proved by the manner in which it is 
necessary to employ them; which is by causing them to sink 
below the surface, and there kept in motion unlike that by 
which the Trout is enticed to leap after a fly. 
It has been questioned how soon it is after going down to 
the sea, before the young of the first season, or of the second 
if they have remained so long in fresh water, are induced to 
