DACE. 405 



quently used as bait for Pike in trolling, on account of its 

 silvery brightness ; but where live bait are required, as for 

 night hooks, Roach are preferable, on account of their being 

 more tenacious of life. 



The length of the head, compared with the length of the 

 head and body, without the caudal rays, is as two to nine ; 

 the depth of the body compared to the whole length, as one 

 to five ; the muzzle pointed ; the mouth rather large, being 

 more deeply cut than in a Roach of the same size ; the 

 nostrils very similar ; the eye not so large, the diameter of 

 it compared with the length of the head being as two to 

 seven ; the back but slightly elevated : the form of the body 

 elongated and elegantly shaped ; the scales considerably 

 smaller than those of the Roach when the two fishes are of 

 the same size : the number of scales composing the lateral 

 line fifty-two, on an oblique line above it eight, and descend- 

 ing from the line to the origin of the ventral fin four. 



The dorsal fin commences rather farther back than in the 

 Roach, the first ray being behind the middle of the body ; 

 the ventral fins rather in advance of the line of the com- 

 mencement of the dorsal fin ; in other respects the fins in 

 these two species are very similar. 



The rays in number are 



D. 9 : P. 16 : V. 9 : A. 10 : C. 19. 



The colour of the upper part of the head and back dusky 

 blue, becoming paler on the sides and white on the belly ; 

 the hides straw yellow ; cheek and gill-covers silvery white ; 

 dorsal and caudal fins pale brown ; pectoral, ventral, and anal 

 fins almost white, tinged with pale red. 



