PIERINAE: PIERIS OLERACEA. 1203 



my own and Ostcn Sacken's taken in Colorado and Utah during July and 

 up to August 3, where I found it only above 8500 feet, were all of the 

 euninier type and undoubtedly belonged to a second brood ; and com- 

 parison with the dates at the east makes it most probable that there is also 

 a third brood there. 



Habits, flight and behavior of the butterfly. The butterfly is con- 

 stantly seen flying about garden plots in the vicinity of turnip beds, but 

 its native haunts are the borders of thin woods where wild Cruciferae 

 grow. In the White INIountains one quickly notices the difference in this 

 respect between it and P. rapae, the latter confining itself almost exclu- 

 sively to the neighborhood of houses or the high road, in contradistinction to 

 the habits of the present species, which prefers open places in the woods 

 and forsaken roads through them, seldom occurring in the vicinity of culti- 

 vated ground. In keeping with this it seems to be a far more timid 

 species than P. rapae, being very wary of approach and also a swifter 

 species in flight ; it is as if in its partial supplanting by rapae it felt that 

 "every man's hand was against it," and it had become a misotherian. 

 Riley gives the following account of its habits (Report, 1883) : — 



The butterfly flutters about during the clay, especially in the gardens and over the beds 

 of plants upon which its eggs are to be laid. It is said to be remarkably pugnacious in 

 disposition, and whenever a dozen or more are quenching their thirst around a small 

 puddle, a tierce battle is sure to ensue. The butterflies begin by jostling one another, 

 striking their antennae together and flapping their wings, then the meUe commences, 

 and often becomes so deeply interesting that some enemy, a bird or a dragonfly, pounces 

 upon and devours one-half of the struggling combatants before the others have dis- 

 covered the ill-omened presence. 



Harris describes it as flying "slowly and lazily, especially when laying" 

 its eggs. According to Lintner it begins its daily flight at an earlier 

 hour than any other butterfly, often before seven o'clock, and is seen 

 abroad until late in the afternoon. Mr. Lintner has observed its partiality 

 for the blossoms of burdock, and D'Urban speaks of its habit of pitch- 

 ing upon the dead fish and offal lying round his camps in the woods. 



When at rest on a vertical surface, it holds the wings erect, the hind edges 

 of the hind pair resting on the surface, the antennae spread at right angles 

 and parallel to, but raised a trifle above, the line of the trunk ; beyond the 

 curved base they are as straight as a rod ; the trunk is held at an angle of 

 about 45° with the surface, but the abdomen hangs freely. 



One evening after dark Gosse saw in Newfoundland one of these butter- 

 flies resting with closed wings on a stalk of grass ; he threw it into the air 

 repeatedly, but it would not fly ; it merely fluttered to the ground, and 

 made no resistance to his taking it up again. 



Dimorphism. The summer broods of this species are almost pure 

 white, while the spring brood, besides being smaller, has the under surface 

 of the hind wings and of the tip of the fore wings heavily washed with 

 yellow, and all the veins in the same area broadly sprinkled with dark 



