monly takes the temperature of the surrounding water; in some of the swift oceanic Fishes of the Mackerel family, however, such as the Tunny and the Bonito, the blood is found to be 10° higher than the temperature of the surface of the sea, even within the Tropics: the flesh of these Fishes is dark and dense. The blood-disks are sometimes

circular, sometimes oval.

They are larger than those of MAMMALIA and BIRDS; smaller than those of REPTILES, and especially than those of AMPHIBIA.

The irritability of the muscular fibre is considerable, and is long retained. Fishmongers take advantage of this property, to produce rigid muscular contraction, after life has ceased, by transverse cuts and immersion of the muscles in cold water: by this operation, which is called "crimping," the firmness and density of the muscular tissue are increased.

In our next chapter, we shall enter into some details of the instincts and habits of Fishes, and some other matters connected with the Class, of more popular interest than these structural peculiarities, which, we fear, will prove but a dry morsel to many of our readers.

CHAPTER XXVIII.

PISCES (Fishes).

Continued.

As the innate selfishness of our hearts always prompts the question, cui bono?—it may be as well to commence this chapter with a few particulars of the usefulness of FISHES in ministering to our bodily wants. The value of

fish as an article of human food has been appreciated in all nations and all ages. The earliest pictorial records of Egyptian every-day life are largely occupied with the capture and preservation of these animals; various forms of nets, the fish-spear, the hook and line, are all in requisition; and strings of fishes, split and salted, and hung out to dry, remind us of scenes familiar enough to the writer of these pages-the cod-fisheries of Newfoundland. Allusions to the hook and line occur in the most ancient of writings the Book of Job; and, in the Mosaic law, "whatsoever hath fins and scales in the seas and in the rivers" was freely given to Israel for food. The most remote and savage tribes feed largely on a fish diet; and the ingenious devices and implements employed by the islanders of the Pacific Archipelago far exceed in variety,

and in their elaborate effectiveness, those produced by European art. Every sea, from the Pole to the Equator, is stocked with fishes; they abound in the rivers and lakes of all climates; even the “tarns” and little basins scooped out of the summits of mountain-ranges, hold species of interest and value peculiar to themselves. So that the beneficent Providence of God has thus stored up inexhaustible magazines of wholesome, palatable, and nutritious food, and placed them within reach of man for the supply of his necessity—the stimulus and the reward of industry.

The fisheries of Britain are of national importance; the amount they contribute to the public wealth is immense; and they are regulated, even in many minute details, by repeated enactments of solemn legislation. An enumeration of the species which form the objects of our fisheries is itself startling :—the surmullet, gurnards of half-a-dozen kinds, sea-bream, mackerel, scad, dory, atherine, gray mullet of two kinds, gar-fish, salmon, herring, pilchard, shad, cod, haddock, pout, whiting of two kinds, pollack, hake, ling, burbot, torsk, turbot, holibut, sole, flounder, plaice, dab, eels of three species, conger, thornback, skate of several kinds,—are all taken in quantities and brought regularly to market; not to speak of many other kinds, such as perch, trout, char, pike, carp, roach, tench, &c., which are taken for the table, chiefly from our rivers, for individual amusement.

The quantity of human food thus taken yearly from the water is enormous; an idea of it may be formed from the fact, that, of one species alone, and that a very local one, being confined to the western extremity of our island

the pilchard-the Cornwall fisheries yield 21,000 hogsheads annually. What, then, must be the produce of all the species above enumerated, all round the indented coasts of Britain and Ireland? We have no sufficient data to determine the commercial value of British fisheries; but it has been loosely estimated by Mr M'Culloch at £3,500,000, and by Sir John Barrow at £8,300,000, per annum.

The possibility of capturing fishes of any particular species at any given time, with tolerable certainty, in such numbers as to constitute a fishery, is dependent on certain instincts and habits in such species, leading them to associate in multitudes in particular localities at particular seasons. The most prominent of these instincts is connected with reproduction. It is essential to the hatching of the spawn (or eggs) of most fishes, that it be deposited in comparatively shallow water, within reach of the vivifying influences of light and heat. Hence, as the season of spawning draws nigh, the various kinds leave the deep water, and approach, in countless hosts, the shores, where they are readily seen and captured. And it is a most beneficent ordination of God's providence, that, at this season, they are in the very best condition for food: let the spawn be once deposited, and the fish is worthless. What is more vile than "a shotten herring?"

Any one who will look with curiosity at the "hard roe" of a Yarmouth Bloater, may form a notion of the extent to which fishes obey that primal law, "Be fruitful, and multiply, and fill the waters in the seas" (Gen. i. 22); for this hard roe is nothing else than the accumulation of eggs in the ovary of a female fish: every seed-like grain

an egg, and all to be laid in the course of a few days— the contribution of one individual herring to the population of the seas! It would be no sinecure to count them; but, partly by counting, partly by weighing, approximations have been made to a knowledge of the extent of a fish's family. Six millions of eggs have been estimated to lie in the roe of a single cod!

Now, of course, an immense proportion of this number comes to nothing; perhaps three-fourths of these eggs are devoured by other fishes, or voracious creatures of one kind or other, almost before they well reach the bottom; and of the proportion that is hatched, multitudes find a speedy termination of existence in the maw of their watchful and numerous enemies. For, as a general rule, fishes are universally carnivorous; every species preying without mercy upon all others that it can master and swallow. Some curious examples of this voracity are on record. Mr Jesse speaks of a Pike, to which he threw in succession five Roach, each about four inches in length. "He swallowed four of them, and kept the fifth in his mouth for about a quarter of an hour, when it also disappeared." At a lecture delivered before the Zoological Society of Dublin, Dr Houston exhibited as a fair sample of a fish's breakfast," a Frog-fish, two feet and a half long: in the stomach of which was a Cod-fish, two feet in length; the Cod's stomach contained the bodies of two Whitings of ordinary size; and the Whitings in their turn held the half-digested remains of many smaller fishes, too much. broken up to be identified.

"Harsh seems the ordinance, that life by life

Should be sustained; and yet, when all must die,