32 SALMONID^. 



siderably below the upper profile of the head; the width of this 

 space is one-eighth of an inch shorter than the maxillary bone, and 

 about three-fifths of the postorbital portion of the head. 



The posterior margin of the prajoperculum is slightly rounded and 

 subvertical ; the lower limb is distinct. The hinder margin of the 

 operculum is slightly rounded, and meets the lower limb at a right 

 angle. The distance from the upper end of the gill-opening to the 

 angle of the opercuhim is equal to that from the latter point to the 

 lower anterior angle of the suboperculum. 



The distance of the occiput from the origin of the dorsal fin, if 

 measured back from behind that fin, reaches more than two-thirds 

 of the distance between the adipose and the root of the caudal. The 

 dorsal fin is longer than high, and possesses thirteen rays, of which 

 the first and second are rudimentary^ and covered by the skin, the 

 third simple and shorter than the following one, which is the first 

 branched ray and the longest of the fin: the last ray is cleft 

 thTOughout. 



The anal fin is higher than long, and consists of twelve rays, the 

 first and second being rudimentary and covered by the skin, the third 

 simple and shorter than the fourth, which is branched and attains 

 the utmost height of the fin. 



Pectoral shorter than the postorbital portion of the head by one- 

 fourth of an inch or half the diameter of the ej^: ventral very 

 slightly shorter, its length being about three-sevenths of the distance 

 of its root from the vent ; its outermost ray is vertically opposite the 

 ninth of the dorsal. 



Posterior margin of the caudal fin slightly rounded. 



There are 117 transverse series of scales, counted immediately 

 above the lateral line ; the transverse series descending obliciuely 

 backwards from the origin of the dorsal to the lateral line contains 

 thirty scales ; that from the hinder end of the adipose to the lateral 

 line has fifteen scales. 



Upper parts blackish ; sides silvery, with a purple shade ; belly 

 white ; numerous small irregular black spots on the upper half of 

 the body. Opercles and dorsal fin with small round black spots. 

 Caudal and adipose fin and the inner side of the pectoral and ventral 

 blackish. 



Pyloric appendages forty -six. 



Description of a Male Sea-trout from the Tweed, caught in the month 

 of January, during the spaivning-time. 



inches. 



Total length l^ 



Greatest depth of the body 3| 



Length of the head 4 



Girth of the biggest part of the body 8-J 



Least depth of the tail 1| 



Distance between end of snout and eye 1| 



Diameter of the eye | 



