284 THE FRESH-WATER FISHES UF EUROl'K. 



four to six fewer rows of scales below the lateral line, and a few more pylorie 

 appendages. 



The head, exclusive of the caudal fin, is one-quarter of the total length of 

 the fish. It is depressed, broad, and elongated. Radiating striae are con- 

 spicuous on the lower margin of the operculum. The jaws are strong, but the 

 teeth are hardly so strong in proportion. The head of the vomer is wider than 

 long, with a transverse series of teeth behind. The body of the bone has a 

 single series of teeth on a longitudinal ridge, on which three or four are pre- 

 served in a fish twenty-six inches long. The thin scales on the slender tail are 

 angular behind, but not smaller than those on the body. Twelve or thirteen 

 scales descend obliquely forward in a transverse series from the adipose fin to 

 the lateral line. 



The colour is silvery, with a dark back. There are round black spots on the 

 operculum, and X-shaped spots on the sides. 



Salmo venernensis (GVNTHER). 



D. 14, A. 11, P. 1415, V. 9. Scales : lat. line 120, transverse 2834. 



This Trout is common in Lake Wener and other localities in Sweden. It 

 is not migratory, and attains a length of more than three feet. It is valued 

 for food ; but the flesh is less firm than that of the Salmon, and is orange- 

 yellow rather than red. Mr. Lloyd states that many remain in the River 

 Gotha all the year round, though the majority leave in the late spring, and 

 pass the summer in Lake Wener, coming back again in the autumn to 

 spawn. At spawning-time the snout of the male becomes prolonged, and the 

 mandible hooked. 



Mr. Lloyd, who terms it Wenerns-lax, regarded it as the Grey Trout, 

 usually known as Salmo eriox, which had become confined permanently to fresh 

 water ; but Dr. Giinther removed it from that species. He states that the eye 

 is very small, being only one-fourth of the length of the post-orbital part of 

 the head. 



The head of the vomer is triangular, with a transverse series of teeth across 

 its posterior margin. There is a single series of teeth on the body of the 

 bone. In the young these teeth form a zigzag line, and some of them are 

 shed before the fish acquires a large size. 



There are fourteen scales between the adipose fin and the lateral line, 

 running obliquely forward. 



The fish is silvery, inclining to brownish, or greenish on the back. There 

 are more or less numerous small black spots, angular, or X-shaped, on the 

 sides; and rounded spots on the operculum. 



