468 THE BUTTERFLIES OF XEW ENGLAND. 



midsummer, between the July and Octol)er broods, which probably 

 appears near the middle of August. 



Habits, flight, etc The habits and flight of this butterfly closely 

 resemble those of V. cardui, but, although considerably more abundant in 

 some years than in others, it is much less subject to variation in this 

 respect. It selects the same resorts and is likewise very fond of thistle- 

 flowers, as also of dandelion-flowers ; it has also a nearly ecjual activity 

 and will keep on the wing to as late an hour of the day. 



When at rest but on the qui vive, the wings are widely expanded, 

 raised at an ano-le of abovit 15°-20° with the surface of rest ; the antennae 

 are perfectly straight, raised above the plane of the body at an angle of 

 20°-25°, and spread at nearly or quite a right angle. Allien quietly rest- 

 inof, the Avings are placed back to back, and the antennae, raised at an 

 angle of 40° with the body, are spread at an angle of only 50°. It, how- 

 ever, frequently varies from this by gently fanning its wings upward and 

 downward in a self-contented way, about once a second. When, however, 

 the insect is at complete rest, as during the night, the wdngs are not only 

 closely compressed, but the fore wings are hidden by the hinder pair so that 

 the costal edijes of both are continuous, while the antennae are nearly 

 perpendicular, placed at right angles with the body, and spread about 12°. 

 Dr. C. S. Minot also observed, many years ago, the position of the legs 

 when at rest. The middle and hind femora are nearly at right angles 

 with each other, and when on a horizontal surface the whole of the tarsi 

 rest on the ground ; Avhen on a perpendicular support, it touches only the 

 claws to the surface of support. He also observed it clean its antennae 

 by folding the tarsi at a sharp angle and drawing the antennae from base 

 to apex through the crotch thus formed. This is the more remarkable 

 because done with the middle legs. 



Parasites. The caterpillar is attacked by a large ichneumon, I. rufi- 

 ventris (88 : 1 ) , which finally makes its escape from the chrysalis at the end 

 of September. The ichneumon is so large that the caterpillar can support 

 but a single one. I received this parasite from Miss C. Guild of Walpole, 

 Mass., and Mr. E. Norton of Farmingtou, Conn., and have raised 

 it from a chrysalis of huntera sent me by Mr. D. W. Beadle of Ontario. 

 It has also been raised by Messrs. Bowles, Packard and Cresson. This 

 shows how common it is. That sent by Mr. Beadle emerged September 25. 

 The parasite makes its esca})e from the chrysalis case of the butterfly by 

 biting ofi^ the head and a part of the thorax just above the upper shoulder 

 tubercle, leaving only a slight fragment at one side to keep the lid thus 

 formed in place. Even in a chrysalis which lay upon its side during the 

 escape of the ichneumon, it could not wholly discard its ordinary opera- 

 tions, although forced at last to ffnaw out a hole at one side, which it did 

 at the base of the tono;ue and below. Mr. Riley also found among the 



