LIBYTHEINAE: HYPATUS BACHMAXII. 765 



Food plants. Dr. Kirtland conjectured tliat raspberry might be the 

 food plant of the larva, but Abbot long ago found it feeding on the sugar- 

 berry or hackberry, Celtis occidentalis L., one of the Urticaceae ; and 

 Boisduval and LeConte figure it on that plant. It would seem as if 

 Major LeConte knew o;f its food plant either from Abbot or by his own 

 observations, for, in the original drawings Dr. Boisduval showed me, no 

 plant whatever is di'awn or specified. Edwards, Avho alone in recent 

 years has raised it, says that he is not aware that it has any other food 

 plant ; but Celtis does not grow so far north as some of the localities 

 wlicre the butterfly has been found, notably northern New Hampshire. 



Life history. Our knowledge of the history of this butterfly is rather 

 imperfect ; our best information comes from Mr. W. H. Edwards, who 

 says : "It is certain that in this region (W. Va.) the species appears in 

 several successive generations, probably four, that the later butterflies 

 hibernate, and the survivors are on the wing early in May, and probably 

 in favorable seasons, in April. The first generation in descent from the hi- 

 bernating females are on the wing in June, — the second generation in 

 July, — the third in August, and late butterflies emerge from chrysalis in 

 September, and these would be of the fourth generation in descent from 

 the hibernating females. The period from laying of the egg to emergence 

 of the butterfly is from fifteen to seventeen days." In confirmation of this 

 he reports a capture of a worn female before the middle of May, and gives 

 the dates of his captures of all stages for ten years, by which it appears that 

 there is hardly a week in the year from the end of the first week of June 

 to the same part of September that eggs have not been found or they may 

 be inferred as existing, from the discovery of caterpillars a little later. 

 Data from other sources are scarce. Dr. Harris's specimen was taken 

 in Cambridge on June 24. Gosse records one capture in Alabama on 

 July 15 ; Andrews took his at Hoboken September 2 ; Miss ^Nlills that 

 at Hamilton early in August. Dr. Hoy says that it appears in Wisconsin 

 while the raspberry is in flower ; Grote that it is found in Alabama in July 

 and August ; while Dr Chapman states that he took two "rather old" speci- 

 mens in Florida in February. This latter statement and Abbot's record 

 of caterpillars changing to chrysalis on the 29th of April and appearing 

 as buttei-flies in nine days verify Edwards's belief that the imago hiber- 

 nates. For other points in the history of this insect we shall borrow bodily 

 from Mr. Edwards : — 



The e?gs [are] laid siiii^ly on the immature leaves at extreme ends of the branches, 

 and I found . . . that nearly every branch had its egg. . . . Usually one egic is laid 

 at the end of a branch, in one of the forks, on the leaf-stem, but I have seen two eggs 

 on the same stem, and occasionally an egg laid on the under side and middle of a leaf. 

 [The duration of the egg is only four days.] 



Several of the eggs hatched in the glass to which I transferred them. But the 

 larvae were exceedingly delicate, and one after another dropped oft' the leaves till all 



