) SALMON, Salmo, a genus.of fishes of the family salmonida (q.v.), which, as charac terized by Cuvier, has teeth on the vomer, both palatine bones, and all the maxillary bones; and includes numerous species more recently divided by Valenciennes into three genera, salmo, prio, and salar: the first characterized by a few teeth at the end of the vomer; the second by a single line of teeth running down the vomer; the third by two rows of teeth on the vomer, without any remarkable group at its upper end. To many naturalists, however, this division seems too artificial; and the characters, although excellent for distinguishing species, not such as ought to divide genera; an opinion confirmed by the fact, that the teeth are numerous along the vomer in the young of the species, as the common salmon, which finally retain only a group of them at the end. The division made by Valenciennes separates the salmon, the salmon trout, and the gray Or bull trout, the only British species which ascend rivers from the sea, into the two genera salmo and faria; whilst the common trout is referred to salar. A much more natural division, having regard to characters really conspicuous and important, and to the habits of the species, is the simple one of Mr. Pennell (The Angler Naturalist, 1863), which is really nothing more than a formal recognition of groups practically recognized by every one acquainted with the fishes which compose them; "1. The silver or migra tory species (i.e., those migrating to and from the sea); 2. The yellow, or non-migratory species; 3. The charrs, or orange and red-coloured species." The present article is devoted to the first of these groups. The second is noticed in the article TROUT; the third, in the article ClIARR.
By far the most important of the three salmonicla which ascend the rivers of Britain from the sea is the SALMON (salmo salary, in commercial importance far superior to arty Other fresh-water fish, both on account of the abundance in which it is procured in the northern parts of the world, and of its rich and delicious flavor., From aimient,times it has furnished important supplies of food; and the salmon fisheries of Britain have long been a subject of anxious attention to the legislature. Even rivers of Iceland now yield a rent, and are regularly netted for the supply of the British market, to which the salmon are brought, as from other northern regions, fresh, in ice. .Many rivers and streams, also, arc rendered valuable by the salmon which periodically visit them, as affording sport to anglers with which nothing of the same kind is deemed worthy of comparison, and those of Norway, as well as those of Britain itself, are now frequented by British anglers.
The salmon is one of the largest species of the genus, having been known to attain the weight of 83 lbs., whilst salmon of 40 or 60 lbs., and even upward, are occasionally brought to market. Very large salmon, however, are not common, owing to the eager ness with which the fishery is prosecuted. No fish hi, more symmetrical 'or beautiful than the salmon; and its form is admirably adapted to rapid motion even against power ful currents, by the regular tapering from the front of the first dorsal fin both to the snout and to the tail, but more suddenly in the former direction, by the nearly equal convexity of back and belly, and by the perfect smoothness and want of angularity. The head is about one-fifth of the whole length of the fish. The under-jaw of the male becomes hooked during the breeding season with a kind of cartilaginous excrescence, which is used as a weapon in the combats then frequent, woLnds so severe being inflicted with it that death sometimes ensues. The lateral line is nearly straight. The scales are small, and the color a rich buish or greenish gray above, changing to silvery-white beneath, sprinkled above the lateral line with rather large black spots. The opercular bones show a rounded outline at the hinder edge of the gill-covers, which at once dis tinguishes this species from the only other British species that can be confounded with it, the salmon trout and the gray or bull trout. The tail is forked in the young salmon, but becomes nearly square in the adult. The mouth of the salmon is well furnished with teeth; a line of teeth on each side of the upper jaw; an inner line on the palatine bone, two or three in the adult state at the end of the vomer, two rows on the tongue, and one row along the outer edge of each lower jaw-bone. This array of teeth indicates vorac ity, and the salmon seems to prey readily on almost any animal which it is capable of capturing, though it is a somewhat singular fact that the stomach when opened is rarely found to contain the remains of food of any kind: two or three herrings of full size have, however, been found in its stomach; the sand-launce and other small fishes seem to constitute part of its food; and when in fresh water, trout-fry, or the fry of its own species, worms, flies, etc. The angler catches salmon with the artificial fly, or with the minnow or the worm; and no bait is more deadly than the roe of the salmon itself, the use of which is indeed prohibited in British acts of parliament intended for the protection of the salmon fisheries. The eggs of crustaceans have also been found in the stomach of the salmon in such quantities as to show that they form a very consider able part of its food.