LETTER OF DECEMBER 12TH, 1857. 11 



a week or ten clays. There were two pupaa, which I hoped 

 at one time would remain in the chrysalis state until spring, 

 and that I should have the pleasure of sending them to you ; 

 I was much disappointed when I found, about the middle of 

 November, they had also appeared, though exposed to an out- 

 door temperature. I failed to ascertain in what situation the 

 eggs of the autumn brood are deposited, and am at a loss to 

 divine by what provision the "spring brood is brought into 

 existence. When I found the pupa?, October 18th, the 

 locust tree and our other forest trees had begun to shed their 

 leaves, and before all of the brood appeared the tree was 

 entirely denuded. They cannot appear as a general thing, 

 therefore, before the fall of the leaf, although some of them 

 do, and those which remain in the leaves as pupae are doubt- 

 less far removed from their food plant by the winds, when 

 they do make their appearance. Do you think it is probable 

 that the eggs of the autumn brood are deposited on the young 

 buds ? 



Description. Head and salient, frontal toupet, greyish- 

 brown. Antenna dark brown above, whitish beneath, and 

 very slightly annulated with white on each joint. Face and 

 palpi silvery white. Anterior icings golden yellow, base 

 fuscous, *vn\hfour costal and three dorsal or internal streaks 

 silvery white, and all black-margined on both sides: the first 

 costal streak is curved posteriorly, and terminates in a point 

 in the middle of the wing; the second costal, likewise curved, 

 joins the first dorsal streak near its point, the latter being 

 longer and more oblique; the third costal has the curvature 

 of the preceding streaks and unites with the second dorsal, 

 whose curvature is reversed, — in some instances this streak is 

 shown as two distinct spots; the fourth costal and third dor- 

 sal are spots, placed on the margins just before the apical 

 spot, which is black and almost round; the elongated scales, 

 forming the posterior elliptical outline of the wing, are tipped 

 with black; cilia long and grey. Posterior wings dark grey, 

 cilia the same. Al. exp. 2*5 to 3 lines. 



Classification. Having no books of reference treating of 



