INJURIOUS INSECTS. 
7 
If a tree supplies food enough for the larvae 
that are feeding upon it, they will pass the pupa 
state in the rolls of the leaves. The pupa in a few 
days wriggles itself partly out of the leaf fold, the 
pupa case splits on the back and the moth (Fig. i,b) 
escapes. The developement of this insect was 
closely watched last summer, and on June 17, I 
noted the fact that the larvae were fast changing to 
chrysalids. On June 24 the first moths appeared in 
the breeding cages and on the evening of June 29 a 
number of the moths flew to light in my office for 
the first time, and on July 6 the moths were swarm¬ 
ing in the trees in the evening for the purpose of 
egg-laying. The eggs deposited at this time are 
still (April 28) unhatched, so there can be but one 
brood of this insect in a year in Colorado. 
The moth measures about four-fifths of an inch 
from tip to tip of the wings when spread and the 
length of the body is about two-fifths of an inch. 
The predominant color of the fore wings is rust 
brown and the markings are very light yellow, 
almost white. When the wings are spread, the 
most conspicuous markings are a rather large rust- 
red area at the base of the wing, a similarly colored 
broad band extending from near the middle of the 
anterior margin back and outward to or beyond 
the middle of the wing, and a spot near the outer 
margin of the wing. Either side of the band on 
the costal margin is a rectangular or triangular 
light area, the outer one being fully as broad as the 
rust colored band but the inner one narrower. The 
posterior wings are of an uniform smoky or slate 
color. It should be said, however, that the mark¬ 
ings vary a good deal in different specimens. 
