296 



THE FRESH-WATER FISHES OF EUROPE. 



over the sides, and there are small black spots on the dorsal fin and operculum, 

 but the other fins are green. The head is well-shaped, and of medium si/c, 

 while the body is stout. The snout is rather elongated in the male, with a 

 corresponding mandibular hook at spawning-time. The maxillary bone is well- 

 developed. The teeth are in no way remarkable, except that the single 

 series on the vomer alternates to the right and left, and persists through life. 

 The pectoral fin diminishes in relative length with age, and the caudal loses its 

 emargination, and becomes truncated. There are thirteen to fourteen scales 

 descending in a transverse series from the adipose fin to the lateral line. The 

 vertebrae vary from fifty-seven to fifty-nine, and the pyloric appendages from 

 forty-five to fifty-two. 



Salmo carpio (LINNAEUS). The Trout of Lake Garda. 



D. 13, A. 12. Scales : lat. line 123. 



This beautiful Italian Trout was known as early as the sixteenth century, 

 but has been little studied (Fig. 151). It agrees with the larger Lake Trout in 

 form and most characteristics, so that it will be necessary to draw attention only 



Fig. 151. SALMO CAKPIO 



to features in which it differs from them. The maxillary bone in fishes of 

 medium size extends below the hind margin of the orbit. The vomer has three 

 teeth in a triangle on the anterior plate ; and on the middle line of the narrow 

 stalk of the bone, there are thirteen teeth in a simple row, with their points 

 turned back, though occasional specimens may be found in which some teeth 

 are bent to the right or the left. The mouth is rather wide. 



The snout is longer than the diameter of the eye. The border of the oper- 

 cular covering forms a regiilar curve. The number of branchiostegal rays varies 

 by about three on each side, so that the number on the right side is from ten to 

 thirteen, and on the left from eleven to fourteen. The number of short, blunt 



