INHABITANTS OF NEW ENGLAND 147 



among the inoiiiitains of our west, one is found in 

 the Alps of Switzerland, and one in the Hima- 

 layas. Brenthis, however, the other White Moun- 

 tain genus, while occurring as far north as butter- 

 flies are known (two or three species having been 

 found by the very shores of the Arctic Ocean, in 

 Greenland and Grinnell Land), is represented 

 more largely by species occurring in the temperate 

 zone, and we have in New England itself two of 

 such species. In keeping with this distribution of 

 these genera, the White Mountain Oeneis is not 

 only confined to the barren summits of the range, 

 but even, as we have found, to the higher parts of 

 this region, although its food-plant, Carex, is 

 found everywhere above the forest. The White 

 Mountain Brenthis, on the other liand, very rarely 

 occurs in the same district with Oeneis, being 

 almost wholly confined to the lower half of the 

 barren region. Its food-plant, though not known, 

 is presumed to be violets, which are found in 

 scanty numbers in the strictly alpine district, a sin- 

 gle species being found in favorable spots ; but they 

 are sufficiently abundant in the subalpine zone. 



These two butterflies, then, may be looked upon 

 as the oldest inhabitants of New England, which 

 followed the retreating ice-sheet in its progress 



