150 ■ SALMONID^. 



it passes over the base of the pectoral fin, when it proceeds 

 straight to the tail. Head flattened between the eyes. Snout 

 protruded, and in aged individuals with a tubercular enlargement 

 on its extremity. Eyes large ; the antero-posterior diameter of 

 the orbits 1*5, and their distance apart 2'5 ; nostrils contiguous, 

 patent ; the anterior vertically oval, the posterior smaller and 

 rounded. Under jaw shortest, and received into a cavity of the 

 upper. The transverse membrane over the roof of the mouth 

 exceedingly tough and thick ; the numerous curved teeth in the 

 jaws partly concealed by a loose fleshy membrane. Tongue, 

 long, narrow and thick, Avith a series of teeth along the central 

 furrow. Many series of acute teeth along the vomer and on 

 the palatines. 



" The first dorsal fin with its upper margin rounded, sub- 

 triangular, arising somewhat nearer the snout than the 

 extremity of the caudal rays, higher than long, measuring 

 4-5 in height, and 4-0 along the base. It is composed of four- 

 teen rays, the first two short, and imbedded in the flesh; the 

 fourth and fifth rays longest. The adipose fin 1*0 long, and 

 placed over the end of the anal fin. Pectoral fins broad and 

 pointed, five inches long, and arising slightly behind a line 

 drawn from the upper posterior angle of the opercle. It is 

 composed of fourteen rays. The ventral fins, placed nearly 

 under the centre of the dorsal fin, composed of nine rays, and 

 furnished with a thick axillary plate. Anal fin quadrate; its 

 extreme height 4'4, and its base 3'0 ; composed of twelve robust 

 rays. Caudal fin nine inches in extent from tip to tip, furcate, 

 with a sinuous margin. 



" Colour — from a living specimen. All the upper portion of 



