FISHES OF LAKE SUPERIOR. 311 



parison, we have ascertained that the species of Lake Superior, 

 which we here describe, is a species distinct from all others ; 

 that Cr. ocddentalis Dekaj, and Gr. punyitius Storer, are the same 

 species, differing, however, from the Cr. ocddentalis Cuv. This lat- 

 ter will preserve the name which Cuvier gave to it, and the species 

 of New York and Massachusetts will be designated under the name 

 of Gr. Dekayi. 



This is not the place to enter into minute details, by means of 

 which to distinguish the species. We shall soon treat of them in a 

 monograph of all the species of North America, limiting ourselves 

 at present to describing the one collected about the Sault of St. 

 Mary. 



The body is subcylindrical or compressed, growing thinner from 

 the insertion of the dorsal and anal fins towards the tail, which be- 

 comes very thin and slender, widening at the tip for the insertion of 

 the caudal. It is from two inches to two inches and one half 

 long in adult specimens ; its greatest height is at the pectorals, and 

 is contained six times in the length. The outlines of the back and 

 belly are slightly convex ; the former from behind the occiput to the 

 posterior margin of the dorsal fin, where it descends somewhat ; the 

 latter from the lower end of the snout to the posterior margin of the 

 anal, being depressed on the tail. The head, from the end of the 

 snout to the posterior margin of the operculum, is the fourth part of 

 the length, and to the occipital carina one-fifth. The head is sub- 

 conical, generally pointed forwards ; the lower jaw, which somewhat 

 exceeds the upper in the protraction, forms an angle, reentering 

 in the retraction. The teeth are minute ; the fissure of the jaws con- 

 siderable. The eyes, proportionally large, have a diameter of nearly 

 three-sixteenths of an inch ; the distance which separates their ante- 

 rior margin from the end of the snout is a little longer than their diam- 

 eter. The nostrils, which open along this space, are very near the 

 orbits. 



The suborbital bones, only two in number, are far from covering the 

 cheeks. The first protects the anterior margin of the eyes and the 

 lower margin of the nostrils, leaving a bare triangular space between 

 it and the second suborbital, situated below the vertical line which 

 would pass through the eyeball. It does not exceed the posterior 



