1484 THE BUTTERFLIES OF NEW ENGLAND. 



hibernation the color of the body has changed to a very pale vinous tint, 

 not unlike that of many dried leaves, and the head to a dull yellowish 

 brown, in no great contrast to that of the body. 



Pupation. Wiicn, in the early spring, the insect feels the time for 

 pupation approach, it gnaws a passage through the end of its nest and con- 

 structs another — at least in confinement ; probably also in nature, for it 

 would hardly be possible for the imago to escape from such a retreat ; 

 perhaps, as the leaves of the oak fall at about this time, it makes its way to 

 tlie surface of the ground and there constructs a suitable cocoon. Indeed 

 Harris expressly says the "cocoon is composed of stubble." Specimens bred 

 in confinement, finding nothing better than old oak leaves as dry as those 

 they had left, managed from these poor materials to construct a case similar 

 in general form to the one they had left, drawing together and bending 

 the dry leaves into tlie semblance of a cocoon very slenderly protected, 

 constructed of but very few cords and lined with a few glistening tlu-eads ; 

 the surface where they rested immediately previous to their change and the 

 points of support of the Y-shaped shrouds were, however, more liberally sup- 

 plied ; the anterior Y-shaped shroud supported the hinder portion of the 

 mesothorax ; in one instance its stem was 2.25 mm. long and each of the 

 arms 6.7 mm. long; a very thick cord about 4 mm. long, mingled with 

 a web, parallel to the Y-shaped band and having an ill-defined resemblance 

 to it, occupied the posterior extremity and into it the crotchets of the cre- 

 master were plunged. 



Life history. This butterfly is double brooded in the south and prob- 

 ably also in the north, although the records of a second generation in New 

 England are exceedingly few. Here it winters as a full fed caterpillar and 

 during the month of March or at the beginning of April changes to a 

 chrysalis ; in this condition it remains a full month and then takes flight. 

 It is one of the earliest species of Thanaos, making its advent in the first 

 days of May, and was once observed by Miss Guild on April 28th ; the 

 female generally follows the male in a little more than a week and both 

 sexes continue to emerge from the chrysalis imtil after the middle of May, 

 the female probably nearly until the end, and they continue to fly in faded 

 condition imtil somewhat past the middle of June. They are most abun- 

 dant about the middle of May. The eggs are laid between the middle of 

 May and the middle of June and a second brood of butterflies, much less 

 numerous,* appears about the 20th of July continuing through most of 

 August. It is highly probable, from the ordinarily slow growth and 

 habits of the larva and from the small numbers of the second brood, that 

 most of the caterpillars of the first brood feed until autumn, those of both 

 broods becoming full grown between the middle of September and the 



• MaynarJ says It appears "Ingreat numbers In this, as In too many other cases, his obser- 

 In July," as If this were Its special season; but vatlons are mixed. 



