AS A HOME FOR BUTTERFLIES 81 



the grave of countless Bibio femoratus. Of the 

 butterflies alone which I have found ujion the very 

 highest summits are (besides two species immedi- 

 ately to be mentioned, characteristic of the mountain 

 top) the following : Basilarchia archippus, B. arthe- 

 mis, Polygonia interrogationis, P. faunus, P. gra- 

 cilis, Eugonia j. -album, Euvanessa antiopa, Aglais 

 milberti, Argynnis atlaiitis, Brenthis myrina, B. bel- 

 lona, Phyciodes tharos, Incisalia niphon, Cyaniris 

 pseudargiolus, Pieris rapae, Jasoniades glaucus, 

 Thanaos icelus, and Limochores taumas, — in all, 

 twenty species. 



It will require still a good deal of field-work to 

 determine how far up the mountain side these 

 forms habitually breed : for, as given, the list is 

 merely that of stragglers of an inquisitive turn of 

 mind. 



It is far more interesting, perhaps the most in- 

 teresting point in the geographical distribution of 

 New England butterflies, to find that there are two 

 butterflies living exclusively on these inclement 

 mountain heights. One of them, the White Moun- 

 tain butterfly (Oeneis semidea), is known else- 

 where only on the summits of the highest peaks of 

 the Rocky Mountains in Colorado, where it does 

 not appear, apparently, below an elevation of about 



