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If the number of component members in any Family were the sole criterion of its importance, the present group would occupy a much less space in our pages than the preceding, containing, as it does, barely one-third of the number of its species. Yet when we think of the various Salmons and Trouts of Europe and America, and add to them the excellent and beautiful Char, the Smelt, small but delicious, the Grayling, Vendace, Gwyniad, Powan, and Pollan, the Capelin of Newfoundland, and multitudes of other foreign species unknown by English names, but valuable as the food of man, we shall be ready to acknowledge that the Salmonidæ constitute a very important and useful Family in the great Class of Fishes.

The typical Salmons are distinguished for the graceful, swelling symmetry of their form; thick and plump in the centre, and tapering to each extremity. Their body is covered with large and well-formed scales; all the rays of their fins are soft; behind the dorsal there is a small spurious fin, consisting of a doubling of the skin filled with fatty substance, but destitute of rays; this is usually known as the adipose (or fat) fin. In general the mouth is well furnished with teeth; their intestine has many cæcal appendages; and they all have an air-bladder.

The well-known fishes of this Family are powerful, bold, and voracious; in general, however, they do not prey upon other fishes, but