THE CANADIAN ENTOMOLOGIST. 43 



cases extending back to posterior part of joint 5, leg and antennae cases 

 not so far. Duration of this period from 10 to 13 days. 



For several years the larvae of this species have been taken from the 

 willows here, when nearly full grown, in September, and the moths 

 obtained from them in the spring, but not till last spring (1884) did I 

 succeed in taking the larvae through all their stages. In 1883 eggs were 

 obtained in large numbers, but they did not hatch, not for lack of being 

 fertilized, because the larva developed inside the eggs to near the time for 

 hatching, as could be seen through the shell. Two or three of them even 

 came out, but in so weak a condition that they did not eat. I think they 

 must have been affected by the disease that seemed to affect all Lepidop- 

 teral life that year. 



These eggs were obtained May 1 1 th, and the imagines were produced 

 from July 7 to 13. There are two broods in a season, the larvae feeding 

 on willows (Salix 7iigra), the last brood hibernating in the pupa state. 

 In feeding they fasten the leaves of the ends of a twig together and feed 

 in this larvarium, usually several feeding together. They do not pupate 

 in this, but in the breeding cage spin close cocoons of brown silk in the 

 corners of the box. 



As a species this stands close to inclusa. There are several points of 

 difference that seem to be permanent. It is of smaller size, out of a large 

 series of reared and captured specimens none of the females being as 

 large as all my females of inclusa, the most of them smaller than the 

 males of that species ; the males being proportionally smaller than the 

 males of inclusa. In color the females are lighter than the inclusa 

 females, the oblique transverse shades more brown tinted and less orange 

 tinted ; the ante-apical orange that in inclusa is a distinct patch across 

 four or five subcostal interspaces separated by the veins, is in palla a 

 mere stain, in no examples a defined patch, and in some scarcely dis- 

 tinguishable. The males average darker than the males of inclusa, both 

 fore and hind wings being more of a brown of the vandyke-brown order, 

 rather than umber, being more the shade of the male of ijidentata. In 

 this sex the ante-apical orange is more distinct than in the female, but in 

 about nine examples out of ten is still a stain instead of a patch, occa- 

 sionally one showing about" two very small spots that are fairly outlined. 



Palla seems to be the species distributed over this portion of the 

 United States. I found larvae in Nebraska in 1882 that produced this 

 species, and have had a number of specimens sent me from Central 



