168 FISHES OF THE FIRTH OF FORTH. 



Perca fluviatilis.* — The Perch. 



Specific Characters. — Back dusky green ; sides with dusky bands. 



Description. — From a specimen nine inches in length. Body ra- 

 ther deep ; back arched; sides compressed, marked with about six dark 

 brown bands passing from above downwards. Colour above the la- 

 teral line dusky green, below it rather lighter, with a tinge of red ; 

 belly white ; dorsals and pectorals light brown ; anal of a rich scar- 

 let, as well as the ventral and caudal fins ; posterior portion of the 

 first dorsal occasionally black ; irides bright yellow. Teeth small 

 and fine in both jaws, as well as on the vomer, palatines, and pha- 

 ryngeals. First dorsal fin commencing over the posterior half of the 

 operculum, and ending within a short space of the origin of the se- 

 cond dorsal ; all its spines sharp and stout ; the third and fourth the 

 longest ; the remainder gradually decreasing. Second dorsal fin soft 

 and flexible, with each ray, except the first, branched at the summit. 

 Anal fin commencing in a line under *the fourth ray of the second 

 dorsal, and terminating under the last ray but three of the same fin ; 

 first two rays spinous, shorter than the third, which is soft and flexi- 

 ble, as well as the remaining rays in that fin. Pectoral fin taking 

 its origin in a line under the second ray of the first dorsal, and ter- 

 minating in a line under the ninth or tenth ray of the same fin. Anal 

 fin placed rather behind the origin of the pectorals ; first two rays 

 spinous, much shorter than the others, which are branched and flexi- 

 ble. Tail forked ; the middle ray rather more than half as long as 

 the longest ray in the same fin. Margin of the preoperculum finely 

 serrated, the teeth being stronger on the lower border ; operculum 

 triangular, terminating behind in a long flattened point. Body co- 

 vered with hard scales, strongly ciliated at their free margins, render- 

 ing a roughness to the surface of the fish when the hand is passed 

 from tail to head. Lateral line commencing over the operculum, tak- 

 ing a course nearly parallel with the line of the dorsal curve, and 

 ending at the base of the middle caudal rays. Number of fin rays — 



1st D. 14 ; 2d D. 16 ; P. 14 ; A. 10 ; C. 17 ; V. 6. 



The only British fish it is likely to be mistaken for is 

 the Bass, the tongue of which is covered with teeth ; where- 

 as that of the Perch is perfectly smooth. 



* Perca fluviatilis. Cuvier et Valenciennes, Hist. Nat. des Poiss Yar- 



rell, Brit. Fishes — Pennant, Brit. Zool.— Donovan, Brit. Fishes Fleming, 



Brit. Animals — Linnaeus, Syst. Nat — Bloch, Ichth — Jenyns, Brit. Verte- 

 brate Animals. 



