46 TROUT, ETC.-FAMILY CLUPEIDE, OR HERRING TRIBE.

deposited in this, are carefully covered up. The common Trout is entirely a fresh-water fish, delighting in rivers which have a rapid current, and abounding also in many stream-fed lakes; it lurks during the day in the deep pools, under the shadow of large stones, or under precipitous banks; and becomes active towards evening, when it begins eagerly to pursue its prey, which seems to consist especially of Insects and aquatic Larvæ, and of small Crustacea, but also of small fishes, and the ova of the larger ones.-The Char is considered as having the most delicate flavour of any of the fishes of this family; it is a lake fish, and is not very common in this country.-The Smelt resembles the Salmon in its habits, but is much smaller; it has been found, however, to thrive very well when confined to fresh water.Several other genera exist in various parts of the world; some of them approach other families in their general structure, and are exclusively marine in their habits.

571. The only remaining family of this order is that of CLUPEIDÆ, or Herrings, and their allies. These have a scaly body like the Salmon's, but no adipose dorsal fin; and there is also a difference in the arrangement of the bones of the jaws. They are for the most part marine fishes; only a few species, as the Shad and White Bait, ascending rivers periodically like the Salmon. The habits of the common Herring, in regard to its reputed migrations, have been already noticed (§ 546); notwithstanding the very circumstantial account given by Pennant, and copied by later authors, it seems now to be well established that the only migration of the Herring is from the deep seas to the shores at the spawning season, and from the shores to the deep seas when this is over. It is a curious and perplexing circumstance, that the shoals of Herrings do not continue to resort to the same localities; but that they will leave some parts of the coast which they had been accustomed to visit with regularity, and will make their appearance on others which they had not previously frequented. Their food consists of small Crustacea and Fishes; and it appears that they do not spare the young of their own race, five small herrings having been found in the stomach of a large female. They usually swim near the surface of the water;

FAMILY CLUPEIDÆ ;- HERRING FISHERY.

47

and, like other fishes whose habit is the same, their gill-openings are large, their respiration considerable in amount, their muscular energy great, and their demand for oxygen so constant, that, when taken out of the water, they speedily die. The Pilchard, Sprat, Shad, White-Bait, Sardine, and Anchovy, are all more or less closely allied to the Herring, the last departing from it most widely. The range of the Pilchard, which abounds on the Cornish coast, is more southern than that of the Herring; and the Anchovy and Sardine replace the Herring in the Medi

FIG. 276-ANCHOVY.

-

terranean, where it is unknown. The importance of the Herring and Pilchard Fisheries is very great.

Some notion of it may be formed from the fact, that nearly 500,000 barrels of herrings only have been cured in one year; of which more than half were exported. The number of persons to whom this Fishery gives employment in various ways, must, therefore, be very considerable, though it cannot be exactly estimated; and the value of the product as an article of export trade is very important. The total number of persons directly employed in the Cod and Herring fisheries of Britain, as Fishermen, Coopers, Curers, &c., was nearly 87,000 in the year 1836. Of the extent of the Pilchard fishery some idea may be formed from the fact, that about 12,000,000 of these fish have been sold for home consumption alone in a single year; and it is said that more than this number have been brought into one port in a single day. The principal centre of the Herring fishery is at Yarmouth in Norfolk; that of the Pilchard fishery is the neighbourhood of the Land's End.

572. With the preceding order is arranged by Cuvier the Lepidosteus or Bony Pike, which has many of the characters of the Pike, with the structure of the head of the Herring. It differs from both these, however, in having the body covered with a case composed of dense bony square scales; which are so fitted together as to form a most complete armour. An in

48

LEPIDOSTEUS.-GADIDÆ, OR COD TRIBE.

creased knowledge of its internal structure, however, and of the fossil species most nearly allied to it (which are very numerous in the older rocks), has led to a very different position being assigned to it. Its skeleton differs in many particulars from that of ordinary Fishes, and presents several points of resemblance to Reptiles; and this approximation is equally remarkable in the structure of the respiratory apparatus,-the air-bladder being double, and communicating with the oesophagus by a regular trachea or wind-pipe, furnished with a glottis at its upper extremity, so as to be nearly as complete as the lungs of the Siren. In regard to the order of Sauroid fishes, of which this is nearly the only genus at present remaining, but which was once the predominant group of Fishes, more will be said hereafter (§ 582). The Lepidosteus is an inhabitant of the rivers and lakes of America, most of the species being restricted to its warmer parts.

ORDER III.-MALACOPTERYGII SUB-BRACHIATI.

573. The Fishes of this order, from the position of their fins, have greater facility of ascending and descending, than the abdominal fishes; and the range of depth inhabited by the same animal is consequently greater,-except where, as in the Flatfish, there is a peculiar adaptation to a residence at the bottom of the sea. The first family is that of the GADIDE, or the Cod tribe; which have a long body, rather slender, and covered with soft scales,—the head, however, being naked. They live for the most part in the seas of cold or temperate climates; and from their size and their tendency to congregate in particular localities, as well as from the wholesomeness and good flavour of their flesh, they are probably more important to Man than any other family of Fish. The Cod fishery on the banks of Newfoundland sends a vast supply to almost every part of the world; and the amount caught on the British shores also is very considerable. The appearance and quality of the fish vary considerably according to the nature of the ground on which it is taken. Its repro

PLEURONECTIDE, OR FLAT-FISH.

49

ductive powers are enormous; the roe of a single female having been estimated to contain nine millions of eggs. Nearly allied to the Cod, are the Haddock, Whiting, Hake, Ling, Rockling, Coal-fish, and others. The first of these is considered as the most delicate of the whole family, when fresh; but it does not take salt well; and for preservation, the Cod and Ling excel the rest.

574. The second family of this order consists of the PLEURONECTIDE, or Flat-fish. These present several remarkable peculiarities of structure; by which they are distinguished, not only from all other Fishes, but even from all other Vertebrated animals. Their body is extremely compressed, or flattened at the sides; the animal, however, does not habitually swim with these sides erect in the water, but usually lies flat on the bottom, one side being in contact with it, and the other being directed upwards. The lower side is generally white, whilst the upper is brown; and the former is commonly (but erroneously) regarded as the belly of the fish, and the latter as its back. The dark colour of the upper surface harmonises with that of the bed on which the fish lie; so as to enable them to conceal themselves from their foes, or to watch for their prey, without being themselves observed. Individuals are occasionally met with, in which both sides are coloured alike; these are said to be "Doubles." It is usually the coloured side which is doubled; though it is occasionally the white one. By a change in the position of the head, both the eyes are brought round to the light side, so as to look upwards, when the fish is lying on the bottom; this change may be designated as a sort of twisting-round; but it also in-. volves an unequal development of the bones on the two sides of the head, which shows itself in the mouth. Of the pectoral fins, too, one is usually larger than the other. The dorsal fin is continued along the whole of the ridge of the back, from the head to the tail; and the anal fin usually forms a like continuous expansion below, sometimes uniting with the ventral fins. These fishes have no air-bladder, and they seem to have little power of rising from the bottom. When disturbed, they will raise themselves into a vertical position, so as to show their white sides; and

50

FLAT-FISH-TURBOT, ETC.

they then dart along with great rapidity; but they soon return to their usual posture, and glide along with a sort of undulating motion, at a little distance from the bottom. The Flat-fishes are very tenacious of life; and the flesh of all of them is very palatable. That of the Turbot is considered as the most delicate afforded by any marine fish. Although most of the species the Flounder and some others occasionally ascend rivers, and thrive in brackish, or even in

are exclusively marine, yet

any one of these, attaining a length of six or seven feet, and a weight of 300 or 400 lbs. Its flesh is rather coarse and dry, but it admits of being salted. In some of the Mediterranean species, the eyes look towards the left side, instead of towards the right; the latter, though the ordinary rule of the family, is sometimes departed from in other species; the individuals that exhibit the unusual formation, being said to be "reversed." As an instance of the extent and importance of the Fisheries, of which this family is the object, it may be mentioned that the Dutch draw about 80,000l. per annum, for the supply of Turbot alone to the London market; and it is estimated that, of the whole quantity brought to Billingsgate, the Dutch is not more than one-fourth.

575. The third and last family of the second division of Softrayed fishes, is but a small one; and consists of a group which is characterised by the union of the ventral fins into a sort of sucker, or disc, that enables them to form a strong adhesion to rocks and other hard substances. In this manner they can remain and find their food, in situations where every other