192 



fin, compared to the small size of all the other 

 fins, renders the grayling unable to stem rapid 

 currents; they are much more prone to go 

 down stream than up, and are never seen leap- 

 ing at a fall like trout. 



In a grayling of ten inches long, the length 

 of the head is to the body alone as one to four ; 

 the depth of the body rather more than equal 

 to the length of the head : from the point of 

 the nose to the commencement of the dorsal- 

 fin, is equal to one- third of the length of the 

 whole fish, to the end of the fleshy portion of 

 the tail; the posterior edge of the dorsal-fin, 

 half-way between the point of the nose and the 

 end of the longest caudal-rays ; the adipose fin, 

 rather nearer the dorsal-fin than the end of the 

 tail : the height of the dorsal-fin, equal to half 

 the height of the body, the first ray short, the 

 next five increasing gradually in length; the 

 sixth ray, nearly as long as the seventh, and, as 

 well as the five anterior rays, articulated and 

 simple ; the seventh ray, and all the rays be- 

 hind it, articulated, branched, and nearly of 

 the same height; the length of the base of 

 the fin, not equal to twice the length of its 

 longest ray : the pectoral fin, small, narrow, 

 and pointed: the ventral fins commencing 

 in a vertical line under the middle of the 

 dorsal-fin; the anal fin commences half-way 



