1214 THE BUTTERFLIES OF NEW ENGLAND. 



Miscellaneous. The male of this species has a very faint but pleasant 

 odor, difficult to detect. I have sometimes done so, but at other times 

 have been unable to perceive it, on rubbing the scales of the upper surface of 

 the wings and immediately smelling the fingers. It comes from the scat- 

 tered androconia. 



Dr. Dimmock tried some experiments (Psyche, ii : 21) with the imago 

 of this insect, to see how it would endure breathing certain gases. Ex- 

 posed for periods varying from one to thirty minutes in an atmosphere of 

 carbonic monoxide, motion ceased in from eight seconds to a minute, was 

 resumed again in from ten seconds to five minutes after removal, and 

 became active in from twenty seconds to three minutes thereafter. The 

 sex, which may account for the differences, was not noted. "They all 

 rubbed their probosces about their legs while recovering, and several 

 . . . exhibited a slight tendency toward paralysis of the posterior limbs 

 during recovery." Immersed in hydi-ogen, the butterfly was rendered 

 motionless in half a minute, and remaining five minutes in the gas, 

 began to move at the end of eight minutes after removal, and to fly 

 "in a weak manner" in two more minutes. One placed in a mixture of 

 eighty parts of hydrogen and twenty of oxygen, and one in equal parts 

 of each showed no signs of weakness at the end of half an hour. 



Mr. Davis pierced some chrysalids of this species with pins, but they 

 hatched, nevertheless, one of them emerging with the pin through its 

 thorax, as if impaled for the cabinet. Many other species, however, ex- 

 hibit similar tenacity of life. 



Parasites. An account of the insect enemies of this destructive but- 

 terfly may well begin with Europe, where the pest originated. The insect 

 is there attacked by vast numbers of Apanteles glomeratus, which issue 

 from the body of the larva, form their cocoons by its side, and emerge as 

 flies in eight or nine days ; of these, in my experience, about two-thirds 

 are females ; about four days later some of the cocoons will yield another 

 hymenopteron, Mesochorus splendidulus, a parasite of the parasitic Apan- 

 teles, and larger than it. Mr. Howard has given me a list of other para- 

 sites, among which is another species of Apanteles, A. rubecula, a solitary 

 parasite on the larva not half grown ; Pteromalus puiiarum, which is one 

 of its chief enemies, and which issues from the chrysalis when it has 

 undergone all its transformations within the body of its host ; the males 

 are generally many times more numerous than the females ; two species of 

 Monodontomerus, M. aerus and M. dentipes ; and finally the other hyper- 

 parasites, Mesochorus aciculatus and Hemiteles fulvipes. Kaltenbach 

 says that A. glomeratus is attacked by Diplolepis niicrogastri. Among 

 dipterous parasites. Dr. Williston finds recorded two species of Phorocera, 

 P. concinnata and P. pusilla, the former of which I have my.self raised 

 there (specimens determined by Loew) : and Exorista vulgaris, the last of 



