240 FIFTH BEPOBT OF THE ENTOMOLOGICAL COMMISSION. 
upon. Foraboifl two days they remain close to their birthplace, eating only the 
parenchyma ofthe leaf, and showing so little inclination to travel that, should the 
leaf by aeoident be detached, they perish rather than search for another. They have 
at this Stage of growth the curious habit, when disturbed, of raising the abdomen to 
a nearly perpendicular position, holding on to the leaf very firmly with their jaws. 
I'hey are at this time of a glossy yellow color, and generally shed the first skin two 
days after birth, the empty skin adhering tightly to the leaf. 
In the second stage, the color of the worms becomes more brownish, and they are 
iimre active, but still remain clustered together upon a single leaf or branch, scatter- 
ing but slightly in proportion as they skeletonize one leaf after another. They yet, 
for the most part, teed upon the under side of the leaf, not touching the upper skin, 
and giving to the leaves a brownish, speckled, and seared app earance, as if covered 
by patches of some brown fungus. The excrement is voided in long, bead-like 
strings, which cover the ground or hang. down from the branches and leaves of the 
infested trees. In another week, or when the larva.* are about half grown, a second 
molt takes place, they preparing for it in the usual manner by firmly attaching the 
anal joints to the leaf. (Fig. 83, e.) In the beginning of the third stage they 
feed indiscriminately on either side ofthe leaf, hot still refuse to touch the epidermis 
ofthe opposite side. The gnawiugs on the upper side at this stage of growth are 
peculiar, being iu the form of crescent Hues with narrow strips of epidermis between 
them ; whereas ou the under side there is no such regularity, and all is eaten but the 
stronger cross veins. I have been unable to trace any further molts. This third 
stage lasts from two to three weeks, the larva scattering more thoroughly and the 
general color becoming quite brown or yellowish-brown. As the worms reach full 
growth (Fig. 83, ddd) the fleshy part of the leaves is entirely eaten so that little 
remains but the principal ribs, and the leaves thus present a very ragged appearance. 
Toward the end of July and early in August the worms cease feeding and descend 
into the ground, burrowing therein and forming a simple oval cavity a few inches 
below the surface. They lie dormaut therein through the fall, winter, and early 
spring months, assuming the pupa state (Fig. 83, i) but about a week before the 
beetles issue. 
Remedies. — Experiments made upon the larva of the imported elm-leaf beetle shows 
that Paris-green water is very effective iu destroying it, in both the larva and beetle 
states : and, while I have had no opportunity of making such experiments with the 
species in question, I have no doubt that it would here prove equally destructive. 
The larva are, throughout their existence, quite sluggish and drop to the ground on 
slight disturbance. A good shaking of an infested tree, therefore, will bring most of 
them to the ground, and experience shows that they have little or no capacity for 
mounting the tree again. This remedy will be applicable to cultivated trees, espe- 
cially before they get too large. 
24. The interrogation — mark butterfly. 
Grapia interrogationis (Fabricius). 
Injuring the foliage of the elm as well as linden tree and hop-vine, a caterpillar, with 
reddish black, bilobed head, and black body covered thickly with streaks and dots 
of yellowish white, transforming into our largest species of Grapta, and marked on 
the under side of the dull hind wings with a golden semicolon. 
I am informed by H. L. Clark, esq., that iu 1887 the elms iu Provi- 
dence were much eaten and disfigured by these caterpillars, and that 
the chrysalids were everywhere to be seeu attached to fences, walls, etc. 
Larva. — An inch and a quarter long. The head is reddish black, flat iu front and 
somewhat bilobed, each lobe tipped with a tubercle emitting five single black pointed 
spines. It is covered with many small white and several blackish tubercles. The 
