GENERIC CHARACTER OF THE TROUT. 15

those fish which have soft-rayed fins, with their ventral fins placed far behind and unattached to the bone of the shoulder. All the SALMONIDÆ have eight fins, namely, two pectoral or breast fins; two ventral fins, on the belly next below the pectorals; the anal fin, behind the ventral fins; the caudal or tail fin; and two dorsal or back fins, the hindermost small, fleshy, and

without rays.

Although the trout in different localities vary considerably both in appearance and quality, it is by no means a solitary opinion that there exists but one species; the difference of form, size, and colour in the trout of different localities being accounted for by the operation of their food and of the water they inhabit. Some naturalists, however, think-and among them is Mr. Yarrell -that more than one species, and that several varieties, of the common trout, exist in this country; and supposing those gentlemen to classify the lake trout and the gillaroo trout of Ireland* in this latter category, they are, perhaps, suffi

* A remarkable peculiarity of the gillaroo trout is the construction of its stomach, which has been likened to the gizzard of a bird, and accounted for from the circumstance of the principal food of this fish being shell-fish, for the constant assimilation of which its stomach has thus become permanently adapted.

As

ciently correct; although it is by no means made clear that even those varieties may not have been derived from the common trout, altered by circumstances and characterised by peculiarities transmitted through a succession of generations, -but not the less varieties on that account.* to species, there can be no doubt that whatever may be the case with naturalists, the unlearned are certainly apt to multiply them, either from an imperfect comprehension of the term, or from being deceived by the external appearance and colours of the fish, from which a hasty opinion ought not to be formed. “The colouring matter," says Sir Humphrey Davy, "is not in the scales, but in the surface of the skin immediately beneath them, and is probably a secretion easily affected by the health of the animal." The soil, the season, and the water undoubtedly exercise considerable influence on the colours of fish, and that the food does so has been satisfactorily proved by an experiment made some years since in the south of England, and thus recorded by Mr. Stoddart: "Trout were placed in three separate tanks, one of which was supplied daily with worms, another with live minnows, and the

* See Salmonia, pp. 65—72.; also, Combe's Constitution of Man; and the Vestiges of Creation.

third with those small dark-coloured water-flies which are to be found moving about on the surface, under banks and sheltered places. The trout fed with worms grew slowly and had a lean appearance; those nourished on minnows, which, it was observed, they darted at with great voracity, became much larger; while such as were fattened upon flies only, attained, in a short time, prodigious dimensions, weighing twice as much as both the others together, although the quantity of food swallowed by them was in no wise so great."* Whatever may be the fact, we are certainly inclined to think, from all that has been advanced by naturalists, that opinions as to different species and varieties should only be formed upon the surest grounds, and should not be received without the greatest caution. What can be said of the opinion of ordinary folks, when even a professed naturalist tells us that "the various names of common trout, sea trout, and salmon trout apply only to differences arising from age, sex, season, the character of the water, and the sorts of food which they can procure." With due deference to this learned authority, we will remark that the names of sea trout and salmon trout are

* Scottish Angler, p. 79. 2nd edit.

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undoubtedly synonymous, and apply to a wellknown and recognised species of the migratory salmonida, but one entirely distinct from salmo fario, the common trout, which, unlike the sea or salmon trout, never changes its abode from the fresh water.

The size of river trout, which, in a general sense, is characteristic of neither species nor variety, varies considerably in different localities and under different circumstances. In brooks the trout of the largest size are seldom above six ounces, while in rivers favourable to their growth, and protected from poachers, they often reach as many pounds. The Thames, among other streams, often produces gigantic specimens—as large as twelve and fourteen pounds; and in many of the rivers of Hampshire, Wilts, and Dorset, they are often taken of five or six pounds. Occasionally the capture of some veritable monster becomes the subject of record, as, for instance, a specimen taken in 1824 in the river Clist, near Topsham, Devon, by a Mr. Hall of that town, which measured thirty-four inches in length and twenty in girth, and weighed more than twenty-three pounds. We have seen an engraving of this portly individual, which, if faithfully represented, must have been a splendid specimen. Many other Brobdig

nagian trout have been chronicled in works on natural history. Mr. Yarrell describes one of twenty-five pounds "that was captured on the 11th of January, 1822, in a little stream ten feet wide, branching from the Avon, at the back of Castle Street, Salisbury." It is, however, by no means clear to us that these extraordinary specimens were all really common trout, for the evidence is doubtful in some cases, owing to the uncertainty about the ability of their captors to distinguish between the large migratory and other species. But an instance has come under our own knowledge which cannot admit of dispute, for the water in which were captured the specimens of which we shall speak is miles from the sea, and has not the slightest communication with it through any of its numerous feeders. We refer to the reservoir of the canal at Chard, in Somersetshire, a piece of water covering some seventy acres, in which common trout weighing six and eight pounds were taken with the net within two years after its construction; and one was found dead on the bank, about the same period, which weighed more than a dozen pounds. These fish must have been supplied from the neighbouring tributary brooks, in which a trout above six inches long is perhaps never seen; and they afford additional