ORDER II. MALACOPTERYGII.
(Soft-finned Fishes.)
The skeleton in the members of this Order is, like that in the preceding, formed of bone. Their fins are, however, supported by flexible, jointed, and branched rays. "This," says Mr. Swainson, "is the chief typical character, and the exceptions are very few. In some, as in the Siluridæ, the first rays of the dorsal and pectoral fins are represented by bony spines, the sides of which are crenated, or toothed, like a saw. In the Flat-fishes (Pleuronectidæ) the rays are semi-spinous; and even among the most typical Families, the first two or three dorsal rays are rigid: yet all these deviations take not from the fact, that the whole of these fishes are known by the absence of spiny rays, placed after the first or second, in any of their fins."[1]
In addition to this character it may be observed that, with few exceptions, the gill-openings are unconfined, and the gills have the structure common to the Acanthopterygii, of fringes resembling the teeth of a comb.
The Soft-finned Fishes are, in general, inferior to the Spinous-finned in the degree of development of those essential characteristics which distinguish a fish from other vertebrate animals they are a step lower in the scale of organic per-
- ↑ Monocardian Animals, i. 226.
