330 THE FRKSIl- WATER FISHES OF EUROPE. 



snout extends slightly beyond the closed jaws. The teeth .are in single rows ; 

 they curve backward, and are developed on all the elements of the jaws. They 

 are smallest on the maxillary bone, but numerous. The vomerine bones are 

 strong 1 , and have a simple curved transverse row of four to six teeth ; flanked on 

 each side with a stronger row of teeth on each of the palatine bones. The 

 tongue is bordered on each side with a row of six to eight curved teeth. 

 The thick mucus skin of the mouth forms projecting folds or corrugations 

 between the rows of teeth ; and in some of these depressions the new teeth 

 can be seen developing. There is no median series of teeth along the hyoid 

 bone. 



The edge of the pre-operculum is far removed from the eye. The operculum 

 is triangular, with its extremity covered by a broad sub-operculum, which reaches 

 farther back. The gill-aperture is very wide. The number of branchiostegal 

 rays is ten on the right, and eleven on the left. Four branchial arches are 

 strongly developed, with very long, slender, finely-denticulated rake-teeth on 

 the concave side. The pseudobranchiae are large and comb-shaped. 



The frontal profile rises from the snout in a flat arch, and then runs nearly 

 horizontally along the back, but the ventral profile forms a regular flat arch 

 to the vent. The dorsal fin may commence rather behind the middle of the 

 body. It is nearly as long as high, and truncated. The adipose fin is opposite 

 the hinder part of the anal, and is rather long and high. The anal fin is as 

 high as the dorsal, but more truncated behind. The ventral fins are shortest, 

 and opposite the termination of the dorsal. The longest rays of the pectoral, 

 which is pointed, exceed those of the dorsal and anal. The caudal fin is forked. 



The scales are much smaller than in either the May Trout or the Salmon 

 Trout. They are elongated, and everywhere of the same size. On the lateral 

 line Heckel and Kner counted two hundred, Giinther one hundred and eighty. 

 The lateral line is nearer to the dorsal than the ventral profile, and slightly 

 curved in its anterior half. The number of pyloric appendages, which is two 

 hundred, distinguishes this fish from all other Salmon. They are short, nearly 

 equal in length, and are arranged on a large portion of the intestine, so as to 

 overlap, like the scales of a fir cone, except in the median line. There are two 

 convolutions to the intestine. 



The colour of the upper part of the head and back is a dark-brownish 

 green, passing into violet, which shades into reddish-grey, while the throat and 

 belly have a clear silvery lustre. The head and body are covered with very 

 small dark-grey or black spots, between which larger round spots of black are 

 seen on the skull, temporal region, and operculum, and on the back towards the 

 lateral line. Higher up, and farther back, they gradually assume a half-moon 

 shape. The dorsal fin has a few black spots at its base, and a dark border above, 



