2(; THE FKESH-WATKK FISHES OF EUKUPE. 



Valenciennes disting-uished a Ferca ilaliea, cliaracterised by bein<j;- free from 

 bands, and by having- the head slightly larger than the common type ; but 

 this is to be regarded as one of the many varieties of the species. The 

 Perch of the Danube, known as Ferca vulgaris, has no better claim to a 

 distinctive name. 



Another variety, found in the Lakes Longemer and Gerardmer, in the 

 Vosg-es, is distinguished by the more elongated body, less elevated back, 

 associated with a number of minor differences in the form of the snout, 

 sub-orbital ])its, and serrations of the pre-operculum, with a scaliness of the 

 cheek. It is usually smaller, and is probably an ill-nourished variety of the 

 Common Perch. 



The usual size of the Perch in England is from nine inches to a foot. 

 Isaac Walton mentions one measuring nearly two feet, and the longest re- 

 corded measured twenty-nine inches. But the head of a reputed Perch is said 

 to be preserved in the Church of Lulea, in Lapland, which is nearly a foot in 

 length, so that the fish, presumably, must have been between three and four feet 

 in length. The weight of large fishes varies from two or three pounds to eight 

 or nine pounds. In Russia they reach eight pounds in Lake Seligher. In 

 Austria the Perch is rarely more than a foot long, and a pound and a half 

 in weight. In the Zeller See it reaches a weight of three to four pounds. 

 In the Swiss lakes the average weight is three pounds, increasing ex- 

 ceptionally to six. In the higher Alpine lakes the Perch is always smaller. 

 In North Germany it attains a larger size in the Haffs on the Prussian 

 coast than in the smaller lakes. It is a common fish in the Baltic ; but 

 in that sea rarely exceeds from half a pound to a pound in weight. 



There are no marked differences to distinguish the sexes ; but the males 

 have the body slightly higher, and relatively shorter. At Salzburg only one- 

 tenth of the fishes caught proved to be males. 



The Perch frequents clear water, and commonly rests among plants at 

 a depth of two or three feet. In Scandinavian lakes it passes the winter 

 in deep water, but on the breaking up of the frost makes for the shore in 

 large shoals. Siebold describes it as living in Lake Constance at a depth 

 of 240 feet, under pressure so g-reat that when it is brought to the surface the 

 fish may be found torn o])en or with the viscera forced into the mouth. In 

 Swiss lakes it is found as high as 4,4U0 feet above the sea. In such positions 

 it never exceeds one pound in weight, though high up in the Jura Mountains 

 it reaches a larger size. The warmer the water the larger the fish. 



It is gregarious when young, and is often found in great shoals. It 

 feeds on small fishes, worms, larva' of insects, fresh-water Crustacea, and 

 amphibians. Perch will even attack and kill water-rats. Like all voracious 



