Back dusky green; sides with five transverse dusky bands.
P. fiuviatilis, Linn. Syst. Nat. torn. i. p. 481. Block, Ichth. pl. 52. Don. Brit. Fish. vol. in. pl. 52. Flem. Brit. An. p. 213. Perch, Will. Hist. Pise. p. 291. tab. S. 13. f. 1. Penn. Brit. Zool. vol. iii. p. 254. pl. 48. no. 124. Id. (Edit. 1812). vol. iii. p. 345. pl. 59. Bowd. Brit. fr. wat. Pish. Draw. 5. Yarr. Brit. Pish. vol. i. p. 1. Perche commune, Cuv. et Val. Poiss. torn. ii. p. 14. Cuv. Reg. An. torn. ii. p. 132.
From twelve to sixteen inches.
(Form). Body compressed; back much arched, highest over the ventrals, the depth at that part equalling nearly one-third of the length, caudal fin excluded; greatest thickness half the depth: head about one-fourth of the entire length, including caudal: nape depressed, the back rising rather suddenly behind; profile gently falling from the forehead towards the end of the snout: jaws nearly equal; teeth in both jaws, as well as on the vomer, palatines, pharyngeans, and branchial arches: head and cheeks for the most part smooth, the latter covered with small scales: preopercle rectangular; the margin finely serrated: opercle triangular, terminating behind in a sharp point; the subopercle reaching beyond it: gill-opening large: lateral line nearly parallel with the line of the back, its course at about one-fourth of the depth*: first dorsal fin commencing in a line with the terminating point of the opercle; the fourth and fifth rays longest; those on each side gradually decreasing; the last, or last two, in the fin small and inconspicuous; height of the longest rays nearly equalling half the depth of the body: second dorsal close behind the first, only a small space intervening; first ray spinous, not half the length of the second; third and fourth longest; the succeeding ones slightly decreasing; all the soft rays, except the first, branched: anal commencing rather more backward than the second dorsal, and not extending so far towards the caudal; two first rays strongly spinous, much shorter than the others, which are all branched and articulated: caudal forked: pectorals about two-thirds of the length of the head; the middle rays longest, those on each side decreasing; the first two and last three simple, the others branched: ventrals placed a little behind the pectorals, equal to them in length; the first ray strongly spinous, shorter than the others, which are all soft and much branched: number of rays in the respective fins, vent in a line with the commencement of the second dorsal. Number of vertebrae forty-two. (Colours). Back and sides dusky green, with from five to seven dark transverse bands; abdomen white, tinged with red: ventrals bright scarlet; anal and caudal fins somewhat paler; dorsals and pectorals dusky, tinged with red; often a conspicuous black spot on the webs connecting the four last spines in the first dorsal.
* The course of the lateral line is said to be at half, one-third, one-fourth, etc. of the depth, when the distance from the line of the back to the lateral line equals half, one-third, one-fourth, 4c. of the depth of the body.
D. 14 or 15 - 1/13; A. 2/8; C. 17, and some short ones; P. 14; V. 1/5*.
Common in lakes, rivers, and streams. Found, according to Cuvier, throughout all the temperate parts of Europe, and a great part of Asia. Often, but not always, gregarious. Feeds on worms, insects, small Crustacea, and the fry of other fish. Seldom attains a greater weight than four pounds, but has been known to weigh as many as nine. Spawns in April or May. A monstrous variety, with the back hunched, and the lower part of the back-bone next the tail much distorted, is mentioned by Pennant as found in a lake in Merionethshire.
(2. Labrax, Cuv).