FISHES OF LAKE SUPERIOR. 347 



simple but articulated, and almost as long as the following ; being 

 higher than it is long, this fin has a triangular form on account of its 

 posterior margin, which is low and inclines on the back. The adi- 

 pose is broad, covered with small scales on its basis and opposite to 

 the posterior half of the anal, of which it does not attain the extrem- 

 ity. The anal, as long as it is high, occupies the middle of the space 

 between the anus and the basis of the caudal ; it has, like the dorsal, 

 two spinous rudimentary rays in its anterior margin, and one soft ray 

 more. The caudal is furcated and ample ; small scales encroach 

 upon its basis. The ventrals are large, with their terminal margin 

 straight ; they are almost as long as the dorsal is high ; the anterior 

 margin opposite to the twentieth ray of the dorsal contains a small 

 spinous rudiment hidden beneath its membrane ; the cutaneous appen- 

 dix of the upper margin is very small. The pectorals are elongated, 

 spindle-like, and proportionally small. 



Br. 9 ; D. II. 11 ; A. II. 12 ; C. 7, 1. 9, 8, I. 7 ; V. 12 ; P. 

 16. 



During the early age, when its size does not exceed eight inches, 

 the slender form is the predominant character of this fish. The line 

 of the back and that of the belly being then very little prominent, and 

 the outline of the head passing in direct continuation to that of the 

 body, there results a harmonious whole in the proportions of these two 

 regions. The compression of the body is already very marked ; the 

 head is already pointed and forms one-fifth of the whole length, not in- 

 cluding the caudal fin. The rostrum is truncated but rounded, and 

 exceeds the lower jaw. The nostrils are placed at equal distances 

 between its extremity and the eye. The greatest height slightly ex- 

 ceeds the length of the head. The characteristic form of the fins may 

 already be remarked ; there being one ray more or less in the one or 

 the other of the fins. The ventrals are placed somewhat more for- 

 wards relatively to the dorsal, their anterior margin being perpendicu- 

 lar to the fifth or sixth of its rays. The same complete development 

 is also observed in the opercular apparatus ; the operculum alone pre- 

 sents this slight difference, that its height sometimes exceeds a little 

 the length of its lower margin ; the breadth of the suboperculum is also 

 subject to some variations. The scales at this period are thin and fall 

 off easily, but we may recognize already the different characters which 



