940 THE BUTTERFLIES OF NEW ENGLAND. 



vicinity is enough to cause the tubes to plfiy rapidly, and one glolnilo to follow 

 another, sometimes without a retracting of the membrane, and before the near ap- 

 proach of the ants. I have counted six emissions in seventy-live seconds. The tubes 

 are usually expanded when the ants are away from the last segments, and are re- 

 tracted ^v hen they come near. I counted the length of these periods of complete and 

 (iui(!t expansion, ten, twenty, ftfty and to eighty seconds, the period always ending 

 with the approach of the ants. I experimented . . . placnig larvae . . . upon stems of 

 the growing plants, where the ants had access to them. . . .As soon as the ants discov- 

 ered [one of theml , there was an immense excitement and a rush for the last larval seg- 

 ments. The larva forthwith relieved itself by the excretion of the fluid, and the tubes 

 stood out with tops expanded between the periods. If I placed a fresh larva on a stem 

 on which were no ants, there was no excitement in the larva, no appearance of the tubes, 

 and no movement [in the median gland]. If ants were now transferred to the stem at 

 once the larva changed its behavior. 



It is only in the later stages that the ants attend the caterpillars, or any 

 fluid is excreted from the median gland, though the -organs are certainly 

 present at an earlier stage. Mr. Edwards finds the attendance to be also 

 confined to the summer broods of catei'pillars, or at least to those on Cimi- 

 cifuga, and judges that the caterpillars feeding on dogwood or Actinomeris 

 can not exude so sweet a fluid, the flower of Cimicifuga being "of exceed- 

 ing sweetness," while Actinomeris "has a dry flower, bitter to the taste." 



Life history. This polymorphic insect is the first of our native but- 

 terflies to appear fresh from the chrysalis in spring. The earliest speci- 

 mens — of the form lucia — gladden our eyes in Massachusetts about the 

 middle of April, although often delayed a week by inclement weather ; 

 the earliest recorded date is that of April 14 (West Roxbury, Faxon). 

 This form becomes abundant a week after its advent and continues so 

 throughout the first half of May, when it begins rapidly to decrease 

 and by the end of the month is very seldom seen. C. p. violacea, however, 

 follows hard after it ; this form — the alter ego of the preceding — makes 

 its advent during the first week in May, occasionally not until the tenth 

 or later, both sexes becoming abundant toward the end of the month, and 

 it still remains upon the wing throughout June ; one specimen was taken 

 in Walpole, N. H. (Smith) as late as the 7th of July. 



The appearance of this brood (lucia-violacea) is greatly delayed in 

 northern New England. Thus in Maine its usual appearance is post- 

 poned until the middle of May, and in the White Mountains, where 

 it is extremely abundant, females are rarely seen before June and in 

 some years one may only find a dozen males in a day on the last 

 of May. So, too, both here and in elevated localities farther south it 

 is equally late in its disappearance, for male specimens of the form lucia 

 (rubbed indeed) have been taken in Williamstown, Mass., as late as the 

 middle of June (Scudder), in the White Mountains not uncommonly up 

 to the 17th of the month (Scudder), and occasional specimens even on 

 the 28d-24th (Sanborn), or faded, on the 26th (Morrison). 



The earliest males of the next form, C. p. ueglecta, appear at or shortly 



