4 -THE WHITEFISHES OF NORTH AMERICA. 



By Barton W. Evermann and Hugh M. .Smith. 



GENERAL REMARKS. 



The whitefishes constitute one of the most interesting and important 

 groups of food-fishes inhabiting the fresh waters of the Northern 

 Hemisphere. In North America they are especially numerous as to 

 species and individuals in the States forming the northern boundary 

 of the United States, in the British possessions, and in Alaska, where 

 there is scarcely a lake or river of importance in which the whitefishes 

 are not represented by one or more species. 



The distribution of these fishes, their geographical and individual 

 variations, and their habits are perhaps as little known as are those of 

 any group of fresh-water food-fishes of North America. Only two or 

 three of the numerous whitefishes have been studied with even approxi- 

 mate completeness, and there is much yet to be learned regarding even 

 the best-known species. 



The close relationships of many of the whitefishes make a careful 

 study of actual specimens the most essential step toward a fuller knowl- 

 edge of these fishes. To the scarcity of specimens in collections, and, 

 in the case of most species, the absence of complete series of examples 

 representing different sexes, ages, conditions, .seasons, etc., may be 

 largely attributed the general deficiency of recorded information 

 regarding the species of this group. 



The United States Fish Commission has recently come into posses- 

 sion of a large amount of new material relating to the whitefishes of 

 the Great Lakes basin and the specimens and data are available for a 

 preliminary study of the group. It is not intended, however, to present 

 a complete account of these fishes, since much more information will 

 be required before such an effort will be warranted. In the present 

 paper we have endeavored to give careful detailed descriptions of all 

 the species of this group found in North America, together with what 

 is now known of the geographic distribution of each. We consider 

 most in detail those species found in the Great Lakes basin, but for 

 purposes of comparison, and that the paper may be as complete as is 

 now possible, we have included all the species of North America. 



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