ORDER I. BONY FISHES. ACANTHOPTERYGII (SPINY-FINS). 145 
originally took the idea of those vessels which are intended to sail with the 
greatest speed; but the progress of the swiftest sailing ship, with the adyan- 
tage of a favorable wind, is far inferior to that of fishes. Ten or twelve 
miles an hour is no small degree of rapidity in the sailing of a ship; yet 
any of the larger species of fishes would soon overtake her, play round her, 
as if she did not move, and even advance considerably before her. The 
senses of fishes are remarkably imperfect; and, indeed, that of sight is 
almost the only one which, in general, they may be said to possess. 
Since the time of Linnwus, several attempts have been made to classify 
these numerous inhabitants of the watery element, and a number of systems 
has appeared, which are more or less entitled to respect. That of Professor 
Agassiz, founded on their scaly covering, is a very ingenious method, and 
extremely useful in determining fossil species, but is not so applicable to 
existing fishes as that of Baron Cuvier. We have chosen to follow the 
latter, therefore, in this work. He first separates them into two grand 
divisions, —the Bony Fisues and the Carritacinous Fisnes, — the for- 
mer of which he arranges in six orders, and the latter in two. 
BONY FISHES. ORDER I. ACANTHOPTERYGII (Spiny-fins). 
The larger number of known fishes are comprised in this order. “ Their 
characters are spinous rays in the first dorsal fin, if there are more than 
one, and spinous rays in the first part, if there is one only; but sometimes, 
instead of a first dorsal, they have free spines, without any connecting mem- 
branes. The anal has also its first rays spinous; and there is, generally, 
one such ray in each ventral. By the first ray of a fin is meant the one 
nearest the head.” 
Prrcipx&.— The Perch Family. This tribe is distributed over all parts 
of the globe, and is distinguished, as a general thing, by its brilliant tints, 
while some of the Perches are noted for their very gorgeous colors. Nearly 
all of them are delicate eating, and as much sought after as the trout, pick- 
erel, or bass. 
They have an oblong body, covered with rough or hard scales, with the 
gill-lid, or gill-flap, or often both, toothed or spinous in the margins. They 
are mostly thoracic, or have the ventral fins under the pectoral, and are sub- 
divided according to the number of gill-rays. Those in the first division 
have seven rays in the gills, two dorsal fins, and the mouth is furnished with 
rows of extremely minute teeth. 
Genus Perca.—In this group is the P. fluvialis, or common Perch, 
