60 



VT.TiCIDJE. 



c. Adult: female Hkclcton. Ohio. From Mr. Frank's Collection as 



I'erca americarui. 



d. Adult: stuffed. Canada. 



e. Adult. N. America. From Mr. Warwick's Collection. 

 /, fj. Adult. N. America. From Mr. Warwick's Collection. 



h. Adult: stuffed. N.America. Presented by Edw. Doubleday, Esq. 

 i,1c. Adult: skins. Montezuma, U.S. From Dr. Pamell's Collection. 

 I. Intestines of specimen c. 



SJceleton. — The structure of the single bones of the skull is exactly 

 the same as in the Common Perch ; the slight differences are the 

 following : the radiating streaks on th<i upper surface of the head and 

 on the operculum, which are tfj be seen abjo in the Common Perch, arc 

 here deeper and more developed ; the spines of th(.' operculum are 

 more acute, and there in beneath the longest a third, much smaller, 

 but very conspicuous ; there are eight spinous teeth along the lower 

 limb, directed forwards. Vert. 21/20. Tho first interhajmal is 

 attached to the twenty-second vertebra, as in the Common Perch ; 

 and from an examination of the skeletons, I am still more incHnod 

 to consider both i/j be varieties of one and the same species. 



Var. Pkeca acuta. 



Cuv. l<f Val. ii. p. 49. pi. 10; Richardson, Faun. Bor.-Amer., Fishes, 

 p. 4 ; iJekay, New York Fauna, Fishes, p. 6. pi. 68. f, 222. 



D. 13-14 1 i;. A.f 



Total length equal to 3-| the height of the body. Inferior edge 

 of operculum with a few rather strong denticulations ; inferior edge 

 of ])ncoperculum with numerous weak spinous teeth ; operculum 

 striated ; transverse rows ? ; transverse line ?. No black spot on the 

 first dorsal fin. 



Lake Ontario. 



3. Perca gracilis. 



Cuv. ^ Val. p. 50; Richardsrm, Faun, Bor.-Amer., Fishes, p. 4. 



D. 13 I ^. A. I-. 



I 14 



Total length equal to five times the height of the body. Inferior 

 edge of operculum entire ; edges of pra^operculum with numerous 

 nearly equal, very small spinous teeth; operculum striated; m(jre than 

 70 transverse rows of scales ; transverse line ^. A small black 

 spot on the hinder part of the dorsal fin. 



Lake Hkancateles (system of Ontario) ; Canada. 



a. Adult: stuffed. Canada. 



Tills species is considered by Holbrook to be a variety of Perca 

 Jlavescens. 



