THE WHITEFISHES OP NORTH AMERICA. 319 



missioner of Pish and Fisheries for 1872-73. It is not known from 

 any of the Great Lakes except Michigan. All of the specimens of the 

 so-called bluefin or blackfin of Lake Superior which we have seen are 

 the longjaw (A. prognathus). 



The only specimens of the blackfin not from Lake Michigan which 

 we have seen, and, indeed, the only ones existing in collections, are two 

 line examples (Nos. 43099 and 43100, U. S. Nat. Museum) obtained 

 by -lames R. B. Van Cleave in Miltona Lake, Minnesota, where the fish 

 is reported to be abundant, and two others (Nos. 22117, IT. S. Nat. 

 Museum), secured in one of the lakes at Madison, Wis. The Miltona 

 Lake specimens have been described by Dr. Lean (Forest and Stream, 

 June 2, 1894), and we agree with him in regarding them as not different 

 from the Lake Michigan blackfin. The Madison specimens also agree 

 very well with those from Lake Michigan. 



The blackfin is probably the most abundant fish of commercial 

 importance in the deeper waters of Lake Michigan. It is found in 

 schools, like other members of the group, and is, at times, at least, 

 associated with lake trout (Cristivomer namaycush), longjaws [A.prog- 

 natlius), chubs (A. hoyi), and common whitefish (('. clupeiformis). 



Up to a comparatively recent date very little was recorded about 

 this fish. Specimens were scarce in collections, and in the National 

 Museum at Washington there were only the four specimens mentioned. 

 The absence of recorded data regarding the fish and its scarcity in col- 

 lections have certainly been due to no lack of abundance of the fish, 

 but rather to the neglect of collectors. As late as 188G, Dr. Goode, in 

 his standard work on American Game and Food Fishes, stated that 

 "at times it comes inconsiderable numbers to the Chicago market, but 

 it is in general a rare species." 



The first detailed reference to the commercial value of this fish and 

 the most complete account of its habits and distribution in Lake Mich- 

 igan were contained in a report on the Great Lakes for 1885, issued 

 by the United States Fish Commission, based on inquiries made under 

 the direction of Mr. E. Edward Earll. 



Spaicning liabits. — The spawning season of the blackfin is the same 

 as that of the common whitefish and the lake herring. The somewhat 

 limited observations thus far made, and the specimens available for 

 examination, indicate a spawning period in November and December. 

 At that time the fish are reported to gather on stony bottom lor the 

 purpose of depositing their eggs, while at other seasons they are said 

 to prefer clay bottom. The specimens from Lake Michigan examined 

 by us were received fresh November 15 and 21. They were taken in 

 gill nets off' Sheboygan on or about November 12 and IS, and examina- 

 tion showed them to be ripe or nearly ripe with spawn; indeed, some 

 were partially spent. 



The blackfin is found in the deep water at all seasons, although 

 during part of the year it frequents relatively shallow water. About 



