LOCHLEVEN TROUT. 11 



exhibit a small ridge in the centre of each, not perceived in 

 other Trout : in its large and strong fins, and in its habit, as 

 stated by Dr. Parnell, of spawning in spring, it differs from 

 S.fario, -which spawns in autumn, and resembles some of the 

 large species of Trout of the great northern lakes. Three in- 

 dividuals of the Lochleven Trout dissected by Dr. Richardson 

 had each seventy-three pyloric cseca, and in one of them fifty- 

 nine vertebrse were counted. The largest of the specimens 

 measured twenty inches and a quarter, including the caudal 

 fin, and two inches less to the end of the scales. 



Dr. ParnelFs description, taken from a specimen measuring 

 one foot in length, is as follows :— " Head rather more than 

 one-fifth of the whole length ; caudal fin included ; depth be- 

 tween the dorsal and ventral fins less than the length of the 

 head. Gill cover produced behind; basal margin of the 

 operculum oblique ; preopercuhim rounded ; end of the max- 

 illary extending back as far as the posterior margin of the 

 orbit. Colour of the back deep olive green ; sides lighter ; 

 belly inclining to yellow ; pectorals orange, tipped with grey; 

 dorsal and caudal fins dusky ; ventral and anal fins lighter ; 

 gill cover with nine round dark spots ; body above the lateral 

 line with seventy spots ; below it ten ; dorsal fin thickly 

 marked with spots of a similar kind ; anterior extremities of 

 the anal and dorsal fins without the oblique dark bands which are 

 so conspicuous and constant in many individuals of S.fario. 

 First dorsal fin placed half-way between the point of the 

 upper jaw and a little beyond the fleshy portion of the caudal 

 extremity of the body ; all the rays branched except the two 

 first ; the third ray the longest, equalling the length of the 

 long caudal ray ; the seventh as long as the base of the fin ; 

 the last considerably more than half the length of the third, 

 equalling the length of the middle caudal ray ; fin even at 

 the end (in many specimens it is concave, with the last ray 

 longer than the preceding one) ; caudal fin crescent-shaped. 



