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maimed or bruised, and a new limb is gradually formed. Like some of the crabs, lobsters are said to be:attached to particular parts of the sea*.
See through this air, this ocean, and this earth,
From Thee to nothing ! Like the amphibious animals, the heart of fishes is unilocular, or consists but of one chief cavity, and their blood is far less warm than that of quadrupeds and birds. The organs of breathing in fishes are called gills, and consist of a vast number of bloodvessels. The generality of fishes are coyered with scales, of various form and size in the different tribes; which seales are analogous to the hair of quadrupeds and the feathers of birds. The chief instruments of motion, the fins, consist of a certain number of elastic rays or processesy;either of one single piece, in the form of a spine, or of jointed pieces. The strong or spiny rays are usually placed at the fore part of the fin, and the soft or jointed-rays towards the back part.
In sbelly armour wrapt, the lobsters seek
By the various flexures of these organs, the movements of fishes are conducted; the perpendicular fins, situated on the back or upper part of the animal, keeping the body in equilibrio, while the tail operates as a rudder at the stern of a vessel, and the side or breastfins as oars.' The stomach is large, and the intestines far shorter than in quadrupeds and birds : the liver is very large, and usually placed on the left side..
The air-bladder, or swimming bladder which occurs in the majority of fishes, is a highly curious and important organ. It generally lies close beneath the back-bone, and is provided with a very strong muscular coat, which gives it the power of contracting at the pleasure of the fish, so as to condense the contained gas, or elastic air, with which it is filled, and thus enable the animal to descend to any depth, and again to ascend by being restored to its largest size. Some fishes are totally destitute of the air-bladder, and are observed to remain always at the bottom; as the whole tribe of what are termed flat-fish. The teeth are, in some tribes, very large and strong ; in others, very small; in some, sharp; in others, obtuse; in some, very numerous; and in others, very few. Sometimes they are placed in the jaws; sometimes, in the palate or tongue; or, even at the entrance of the stomach. The eyes are, in general, large, and very much flattened, or far less convex than in quadrupeds and birds; this structure being better calculated for giving them an easy passage through the water. In return, the central part of the eye, or what is called the crystalline humour, is of a round or globular shape, in order to give the animal the necessary power of vision, and to compensate for the comparative flatness of the cornea.
The organ of smelling, in fishes, is large ; and the animals have the power of contracting or dilating it at pleasure. This sense is supposed to be extremely accute. The organ of hearing differs, in some particulars, from that in other animals, and is modified
according to the nature of the fish. They are entirely
The sounds and seas, each creek and bay,
MILTON. In the Linnæan arrangement of fishes, the under or belly-fins are termed ventral, and are considered analogous to the feet in quadrupeds; and it is from the presence or absence of these fins that the divisions are instituted.
ORDER 1. APODES, or footless fishes, are entirely destitute of ventral fins. The genera are: 1. Muræna, eel-kind. 2. Gymnotus, electric eel. 3. Anarrhichas, sea-wolf. 4. Xiphias, sword-fish. 5. Ammodites, launce. 6. Ophidium. 7. Stromateus. 8. Trichiurus.
ORDER 11. JUGULARES, or jugular fishes, have the ventral or belly-fins placed more forward than the
pectoral or breast fins. The genera are: 1. Gadras, haddock, cod, whiting, ling. 2. Uranoscopus, stargazer. ' 3. Blennius, blenny. 4. Callionymus, etragonet. 5. Traohinus, weever.
ORDER II. THORACICI, ar thoracic fishes, have the ventral fins situated immediately below the pectoral ones. The genera are :- 1. Gymnetrus, cometfish. 2. Echeneis, sucking-fish. 3. Coryphænd, dorado. 4. Zeus, dory. 5. Pleuronectes, founder, plaice, dab, holibut, solé, turbot. 6. Chætodon. 7.. Sparus. 8. Perca, perch. 9. Scomber, mackarel, bonito, tunny. 10. Mullus, mullet *. 11. Acanthurus, thorn-tail. 12. Holocentrus. 13. Sciæna. 14. Trigla, gurnards. .
The antients absurdly believed that the sucking-fish had the power of arresting the progress of a ship in its fastest sailing, by adhering to its bottom.
The sucking-fish beneath, with secret chains,
* In some parts of the Continent, the fishermen endeavour, by making violent noises, to drive the fish into their nets; but these are so cunning, that, when surrounded with the net, the whole shoal will sometimes escape; for, if one of them springs over it, the rest, like sheep, are sure to follow their leader. This circumstance was noticed by Oppian:
The mullet, when encircling seines inclose,
No ship in harbour moored so careless rides,
Though beat by waves, and urged by driving winds. ORDER IV. ABDOMINALES, or abdominal fishes, have the ventral fins placed below the pectoral ones, and chiefly inhabit fresh water. The genera are: 1. Cobitis, loach. 2. Silurus. 3. Exocoetus, Ayingfish. 4. Salmo, salmon, trout, smelt, char, grayling. 5. Esox, pike. 6. Clupea, herring, sprat, shad. 7. Cyprinus, carp, tench, gold-fish, minnow.'
The following lines are poetically expressive of the danger in which smaller fishes are at the approach of the pike :
Beware, ye harmless tribes, the tyrant comes,
And lurks behind his hungry fangs-beware !* CARTILAGINOUS FISHES, improperly admitted into the amphibia by Linnæus, differ from the rest of the fish tribe, in having a cartilaginous or sinewy, instead of a bony skeleton, and in being destitute of ribs. They are divided into two orders, chondropterygii, and branchiostegi.
ORDER I. CHONDROPTERYGII, or such as have no gill-cover. The genera are: 1. Petromyzon, lamprey. 1. Gastrobranchus. 3. Raia, skate, torpedo, stingray. 4. Squalus, shark, saw-fish. 5. Lophius,
* See M'Quin's pleasing · Description of Three Hundred Animals,' p. 257.