The fins of Pteropods are now interpreted as the expanded lateral margins of the foot, termed parapodia, not homologous with the siphonof Cephalopods which is formed from epipodia.
All the fins have a rounded outline; the short dorsal fin is without a spine, but the males possess a very thick and flattened outer ray in the ventral fins.
The pectoral and ventral fins are so articulated as to perform the functions of feet, the fish being enabled to move, or rather to walk, on the bottom of the sea, where it generally hides itself in the sand or amongst sea-weed.
The Trigla polyommata, or flying garnet, is a greater beauty, with its body of crimson and silver, and its large pectoral fins, spread like wings, of a rich green, bordered with purple, and relieved by a black and white spot.
HAKE (Merluccius vulgaris), a fish which differs from the cod in having only two dorsal fins and one anal.
BURBOT, or EEL-Pout (Lota vulgaris), a fish of the family Gadidae, which differs from the ling in the dorsal and anal fins reaching the caudal, and in the small size of all the teeth.
Having no spines to their fins, the Gadids used, in Cuvierian days, to be associated with the herrings, Salmonids, pike, &c., in the artificially-conceived order of Malacopterygians, or soft-finned bony fishes.
Ventral fins below or in front of the pectorals, the pelvic bones posterior to the clavicular symphysis and only loosely attached to it by ligament.
Fins without spines; caudal fin, if present, without expanded hypural, perfectly symmetrical, and supported by the neural and haemal spines of the posterior vertebrae, and by basal bones similar to those supporting the dorsal and anal rays.
The genus Gadus is characterized by having three dorsal and two anal fins, and a truncated or notched caudal fin.
The cod, Gadus morrhua, possesses, in common with the other members of the genus, three dorsal and two anal fins, and a single barbel, at least half as long as the eye, at the chin.
The alimentary sac is simple elegans from the fins of and devoid of caeca.
It is readily recognized by the yellow or orange-coloured spots which are placed in a row along the dorsal and anal fins, and scattered over the body.
They resemble the latter in the elongation of the body, the large number of vertebrae (240 in Gymnotus), and the absence of pelvic fins; but they differ in all the more important characters of internal structure.
In them the dorsal and caudal fins are very rudimentary or absent, and the anal is very long, extending from the anus, which is under the head or throat, to the end of the body.
The most marked case of such inversion in comparative anatomy is that of Carl Gegenbaur (5826-5903), who in arranging the fins of fishes in support of his theory that the fin of the Australian.
One of the causes of these sudden advances is undoubtedly to be found in the acquisition of a new and extremely useful character., Thus the perfect jaw and the perfect pair of lateral fins when first acquired among the fishes favoured a very rapid and for a time unchecked development.
It by no means follows, however, from this incontrovertible evidence that the acquisition either of the jaw or of the lateral fins had not been in itself an extremely gradual process.
The ventral fins are slightly anterior to the origin of the dorsal fin; and the spine consists of from fortyseven to forty-nine vertebrae.
In some individuals the dorsal fin is only half its normal length, in others entirely absent; in others the anal fin has a double spine; in others all the fins are of nearly double the usual length.
Into these fins, which are largely cuticular and strengthened by radiating bars, a single layer of ectoderm cells projects.
Spadella P. Langerhans, with a pair of lateral fins on the tail and a thickened ectodermic ridge running back on each side from the head to the anterior end of the fin.
The centre of the skin between the fins is very narrow and the skins taper at each end, particularly at the tail.
Sharks are caught in enormous numbers with hook and harpoon; the flesh is considered by some to have aphrodisiacal properties; the dried fins and tails are exported to China; the oil is used for smearing boats.
The Jews are forbidden to eat animals other than cloven-footed ruminants; thus the camel, coney, hare and swine were forbidden; so also any water organisms that had not fins and scales, and a large choice of birds, including swan, pelican, stork, heron and hoopoe.
BREAM (Abramis), a fish of the Cyprinid family, characterized by a deep, strongly compressed body, with short dorsal and long anal fins, the latter with more than sixteen branched rays, and the small inferior mouth.
There are no traces either of paired fins or of dermal armour.
They agree with fishes in the possession of median fins, and resemble the large majority of early fishes in their unequal-lobed (heterocercal) tail, but they have no ordinary a.v.l., c., Central.
Latino Coelho, Historia de Portugal desde os fins do XVIII.
The chief products for export are copra, tortoise-shell, mother-of-pearl, sharks' fins and trepang.
In order to meet these peculiarities the travelling organs of aquatic and flying animals (whether they be feet, fins, flippers or wings) are made not of rigid but of elastic materials.
The ventral fin is also elongated, and all the fins are destitute of spines.
The pelvic fins are abdominal in position, long and pointed in shape, and the pelvic bones are connected with the caracoids.
These fins contain numerous (15-17) rays, a feature in which the fish differs from the Acanthopterygians.
In its gorgeous colours the opah surpasses even the dolphins, all the fins being of a bright scarlet.
The larvae are free-swimming and have the pelvic fins elongated into filaments.
The operculum is sculptured with ridges radiating and descending towards the suboperculum; the scales are large, about thirty along the lateral line, deciduous; the ventral fins are inserted below, or nearly below, the middle of the base of the dorsal fin; the dorsal fin has seventeen or eighteen, the anal from nineteen to twenty-one rays.
(c) Pedalionidae, foot represented by two styles, sometimes ciliated; body provided with six hollow-jointed muscular fins for swimming and leaping.
There are two dorsal fins, the anterior near the head, composed of 11-14 feeble spines, the second near the tail with all the rays soft except the first, and behind the second dorsal five or six finlets.
The gobies (Gobius) are small fishes readily recognized by their ventrals (the fins on the lower surface of the chest) being united into one fin, forming a suctorial disk, by which these fishes are enabled to attach themselves in every possible position to a rock or other firm substances.
Numbers on the mud flats at the mouths of rivers in the tropics, skipping about by means of the muscular, scaly base of their pectoral fins, with the head raised and bearing a pair of strongly projecting versatile eyes close together.
They are all pelagic, the foot being entirely transformed into a pair of anterior fins; eyes are absent, and the nerve centres are concentrated on the ven tral side of the oesophagus.