228 THE CANADIAN ENTOMOLOGIST. 



its food-plant is common through most of the State. In south-eastern 

 Michigan I know it so far only from Oakland County, although it probably 

 occurs in the adjacent counties, but less frequently on account of the 

 smaller number of bog areas. Dr. Wolcott* mentions C. epixantkt from 

 Lamberton Lake, in western Michigan. As it was spoken of as flying 

 over shrubby cinquefoil, I have little doubt but that the butterfly was 

 dorcas. 



The home of this species is in British North America, and it has 

 been found in southern Labrador in the east, Sitka and Kodiak (Alaska) 

 in the west, and in the Nahanni Mountains on the Mackenzie River (Lat. 

 62°), the most northerly point. It is known also from localities in between 

 and as far south as Colorado, and colonies probably exist in many of our 

 western cordilleras. Its most southerly limit may possibly be in Arizona, 

 for Potentillafruticosa has been recorded from the San Francisco Moun- 

 tains in that State. 



Regarding the validity of dorcas as a true species, I can best quote 

 the emphatic words of Dr. Fletcher, to whom I sent specimens. 



He wrote in his letter of Jan. 13, 1908 : 



" I have no doubt at all that this is true dorcas, an insect which I 

 have found very rare in collections. It is quite different from cpixanthe. 

 . . . . I think you will see the differences at a glance. Epixanthe 

 is of a duller gray, always pale beneath instead of ruddy fulvous, and 

 regularly slightly smaller than dorcas. The males of dorcas always show 

 more spots above, and have much less of the submarginal band at anal 

 angle of secondaries above. The red markings of this submarginal band 

 beneath are less angular than in dorcas. The two chief characteristics by 

 which dorcas can be separated from epixanthe are the larger size and the 

 much richer ruddy hue beneath." 



In his letter of Feb. 22, 1908 : 



" It is funny to me how few people really understand this species, 

 which they mix up with helloides and epixanthe." 



Again Aug. 6, 1908 : 



" Few of our American entomologists believe in dorcas as a species, 

 some thinking it to be merely he/Ioides, and others epixanthe." 



When one has these three species before him there is little doubt of 

 the distinctness of each. The fact that the food-plants of all three are now 

 known, and that they are different in each case, is of course significant. 



"Robt. H. Wolcott: Butterflies of Grand Rapids, Mich., Can. Ent., Vol. 

 XXV, p. 103. 



