1910] Wagner, Witefish of Silver Laic, Minnesota. 133 



Snout to dorsal fin in length 2.1 2.2 2.0 



Caudal peduncle in head 2.3 2.3 2.2 



Gillrakers in eye 



Gillrakers ..." ? ? 



D 13 I2 I2 



A 12 12 12 



Scales 12-77-9 12-75-9 10-78-9 



All three specimens are very dark. The dorsal and caudal fins 

 are wholly black, the others nearly so. The upper half of the head, 

 and of the body to the lateral line, are very black ; the body is 

 lighter below but still of a decidedly blue tinge. The scales are 

 strongly punctulated with black, except on the surface between 

 the paired fins. There is a distinct notch at the nape. The caudal 

 peduncle is rather short, the body much compressed. 



The form has considerable resemblance to what I consider to 

 be Corcgomts clupeaformis, Mitchill (using- this name in the sense 

 that Jordan and Evermann apply it : Proc. U. S. Nat. Mus., Vol. 

 36, p. 171 ). which occurs in Lakes Superior and Michigan, as 

 well as in Trout Lake, Vilas County, and Stone Lake, Forest 

 County, both in Wisconsin. The Silver Island Lake specimens 

 differ, however, in the following particulars: the depth of the 

 body is greater, the dorsal fin is higher, the caudal peduncle is 

 shorter and higher, the supplemental maxillary is deeper and more 

 nearly semicircular, the pectoral fin is longer, the line of the back 

 is more deeply notched at the nape, and the color as a whole is 

 decidedly darker. 



In a letter last year President David Star Jordan informed me 

 that in his opinion the forms in Lake of the Woods (on the Cana- 

 dian boundary of Minnesota) and off to the northwest were 

 Coregonus richardsonii, Giinther. This species was described by 

 Gunther in 1866, from dried specimens brought from British 

 America, the exact locality being unknown. All we know about 

 this form up to the present may be found in Evermann and Smith's 

 "The Wnitefishes of North America" (Report U. S. Commissioner 

 of Fish and Fisheries, 1894, p. 295). On comparison of the Silver 

 Island Lake specimens with this description it appears that they 

 agree with it quite closely, certainly as closely as any whitefish I 

 have seen will agree with any description extant. We can there- 



