XYMPIIALIXAE: BREXTIIIS MONTIXUS. 607 



they may also retain them until the very end ol' the season is also shown 

 by the observations on the 15th of September. All we can be sure of is 

 that there is a late brood during August which continues into the middle 

 of September; previous to that, owing to the bleakness of the situation, 

 tiierc is probably not more than a single brood, the later individuals 

 of which encroach closely upon the earlier individuals of the second 

 brood ; though it remains to be inquired whether the later brood may not 

 be made up of caterpillars which have shown their tendency to letharo-y 

 by a prolonged instead of a premature hibernation. 



It should be added that in Europe, among the mountain species of this 

 genus, only a single brood has been observed, and that this is found in 

 some in June, or what would correspond to the presumed first brood of 

 the present species ; in others in the latter part of July and early in Au- 

 gust, or what corresponds to the known brood of our mountain species. 

 The European B. thore which flies in June is conjectured by Meyer-Diir 

 to fly only in alternate years. 



Attitudes. When sunning itself on the ground, as it is fond of doin"-, 

 quite as much as of visiting flowers, it rests, as it does on the flowers, with 

 fully or almost fully expanded wings, the costal edges of the opposite front 

 wings nearly in a line, while the antennae, which are nearly straio-ht but 

 slightly arched and with the clubs bent slightly backward laterally, are 

 raised at an angle of 45° with the body and divaricate about 135^, It moves 

 about, whether on the ground or a flower, with similarly expanded wino-g. 

 When at complete rest, the wings are closed, and the costal maro-in of 

 the hind wing is parallel to that of the fore wing and separated from it by 

 a space equal to the distance between the costal and subcostal veins ; the 

 antennae are now straight, raised at an angle of about 55° with the body, 

 and divaricate about 90°. If disturbed in this position, the creature con- 

 tracts itself still more, as it were, by dropping the fore wings so that the 

 costal margin is as far behind that of the hind wings as they were before in 

 front of it. At night, hanging vertically from a horizontal surface, the 

 wings drooped together, the costal edges of all the wings adjoinino- ; the 

 abdomen also hung freely from the thorax between the wings, out of sio-ht ; 

 the antennae, however, spread from each other at an angle of 80°, in a 

 plane parallel to and just in advance of the costal edges of the wings. 



Experiments. I experimented Avith this butterfly, as with Oeneis semi- 

 dea and Polygonia faunus, already noted, and could not discover any 

 difference in behavior between those taken to the summit, ()300', to Jacob's 

 Ladder, 4500', or to the base, 2800'. It should be remarked, however, 

 that the experiment was not tried under quite the same circumstances, as 

 the descent was made deliberately, on foot by the old deserted Fabyan 

 Path, and occupied three hours. 



Desiderata. Plainly the complete life history of this butterfly is a most 



