169 



as not to be readily perceptible except in places. Other char- 

 acters the same as at the beginning of the period. Duration 

 of this period from 8 to 17 days. 



Chrysalis. — Length 1.45 inches; depth through thorax .45 

 inch ; through joint i of abdomen, .43 inch ; joint 2, .44 inch, and 

 from this gradually tapering to the tip. Wing cases extending 

 over joint 5, the legs and antennee reaching the same distance. 

 Cephalo-thorax, wing and tongue cases coarsely shagreened, the 

 abdomen finely punctured, the tip of the last joint very coarsely so. 

 This ends in four hooks, two longer than the others, and two more 

 hooks arising from the punctured portion at a little distance 

 from the four. These hooks were fastened into a bunch of silk 

 in the posterior end of the cocoon. Color dark brown, almost 

 uniformly covered over with a white bloom. Duration of this 

 period from 37 to 45 days. 



The eggs from which the larvae upon which the above ob- 

 servations were made were deposited October 6, 1881, from a 

 female captured a few days before, 29 eggs being obtained. 

 They were kept through the winter in a jelly dish and began hatch- 

 ing April 6, 1882, nearly all of them hatching that day. When 

 first hatched they were very active and continued to be so during 

 the first third of the larva period. They were first fed on the 

 most convenient willow at hand, but this happened to be of a 

 pubescent species which they refused to eat. This was not no- 

 ticed till quite a number had died. A change to the young leaves 

 of Salix Nigra proved more agreeable to their tastes and seven 

 were carried through to the pupa state, six of these producing 

 imagines. On opening the seventh cocoon some time afterward 

 it showed that the moth had emerged from the chrysalis but had 

 failed to get out of the cocoon. The cocoon is formed by fas- 

 tening the leaves together with but very little lining, and that at 

 the posterior end. 



The larvae hatched April 6th, and spun up May 11, 12, 18 and 

 20, respectively. The moths emerged June 23, 24 and 26, making 

 the larva and pupa periods cover a little more than two months 

 and a half. I have never taken this species in June, the usual 

 time being from the first of August to the close of the season. 

 There is scarcely time for the development of another brood from 

 the last week in June to the first of August, and from this fact 

 I am a little suspicious that the development of these was accel- 

 erated by confinement, though they were kept from any direct 

 influence of the sun. Whether there is more than one brood in 

 a season is a question for future observation. The parent moth 

 was of the uniform brown type, but all the progeny were of the 

 form Carissima, some males and some females. 



