268 
THE STUDY OF INSECTS . 
spines along the back, and other shorter ones upon the sides. 
When not eating, the larvae remain close together, some¬ 
times completely covering the branch upon which they rest. 
This species passes the winter in the pupa state. The adults 
appear in June and July. 
The Mocha-stone Moths, Ichthyura (Ich-thy-u'ra).—To 
the genus Ichthyura belong several species of brownish-gray 
moths, whose fore wings are crossed by irregular whitish 
lines. It was these peculiar markings, resembling somewhat 
those of a moss-agate, that suggested the popular name 
given above. The larvae feed on poplar and willow, and 
conceal themselves within nests made by fastening leaves 
together. Our most common species is the following:— 
The Poplar Mocha-stone Moth, Ichthyura inclusa (I. in- 
clu'sa).—The adult (Fig. 318) is a brownish-gray moth, with 
the fore wings crossed by three irregu¬ 
lar whitish lines. The basal line is 
broken near the middle of the wing; 
and the intermediate one forms an im 
verted Y, the main stem of which joins 
Fig. 318. ichthyura inclusa. the third line near the inner margin of 
the wing, making with it a prominent V. These lines are 
bordered without by rust-red ; there is a chocolate-colored 
spot near the apex of the fore wings, and an irregular row 
of blackish dots near the outer margin. The hairs of the 
thorax form a prominent crest, the fore side of which is a 
rich dark brown. The hind wings are crossed by a wavy 
band, which is light without and dark within. 
The eggs are nearly spherical and smooth; they are 
deposited in a cluster a single layer deep on a leaf (Fig. 
319). When the larvae hatch they make a nest either by 
fastening several leaves together or, as is the case when 
they infest poplar, by folding the two halves of a single leaf 
together; frequently in the latter case the tip of the leaf is 
folded in as shown in the figure. Within this nest the entire 
colony lives, feeding on the parenchyma, and causing the 
