82 
FIRST ANNUAL REPORT OF THE 
When 0.18 inch long, the body is of a pale brownish yellow color, and the two horny plates on the body 
are brown, not black, but the head remains black. 
Described from one specimen found in a plum July 28tli, and one (of the larger size) found in Black- 
knot July 22d. The former was wounded ; the latter I isolated in a separate bottle, and subsequently 
bred the moth from it. 
The cocoon spun by the larva is formed above ground, among the plums from which the full-fed larvae 
have made their exit, or is sometimes attached to neighboring substances. It is composed of dark-colored 
silk arranged in the usual elongate-oval form. 
The Pupa I have not seen. 
Mr. C. V. Riley informs me, that according to H. N. Humphreys, ( Genera of British 
Moths,) the larva of a European species of the same genus to which the Plum Motli 
belongs ( Semasia wceberana,) is supposed to feed on the inner tegument of the hark of 
plum-trees, cherry-trees, apple-trees and occasionally laurels. This is only another 
illustration of the law of “Phytophagic Unity,” as I have called it, which has long 
been known to prevail to a considerable extent among the larvae of the Butterflies and 
the Moths, namely, that the same group of Insects affects the same group of Plants.* 
I have shown that this law also holds good among almost all the groups of gall-making 
insects, the gall-makers belonging to the Order of Two-winged Flies ( Biptera ) forming 
about the only exception.! 
Of course it would be premature to talk of any remedy against the depredations of 
this elegant little jewel of a moth, until we know for certain whether as I suppose she 
is a Guest in the Plum, and consequently a neutral; or whether she burrows into the 
Plum on her own account, and is therefore to be treated as an enemy. I hope that —as 
will sometimes happen both with Eastern and with Western juries — the beauty of the 
air defendant has not warped my judgment, and induced me to bring in a verdict of 
“ Not guilty,” when, in reality, she richly deserved to be sent to the Penitentiary. 
INSECTS INFESTING GARDEN - CROPS GENERALLY. 
CHARTER XIV.— The Hateful Grasshopper, (Caloptenus spretus, Walsh.) 
This insect, as will be seen hereafter, is about seven times as destructive to garden 
crops, as it is to field crops ; and it, therefore, falls legitimately within the purview of this 
Report. It has never yet, so far as is known, invaded this State ; and I do not believe 
that it ever will or can. Still, as many of our farmers and gardeners in Illinois have an 
idea, that it may not improbably, at some future time, pass from Missouri and Iowa 
into Illinois—just as the notorious Colorado Potato-bug (Boryphora 10 -lineata, Say) 
has done —it may be worth while to investigate its Natural History, and to demonstrate 
the improbability of its ever crossing the Mississippi in the course of its Eastward 
progress. It is the province of Economic Entomology, not only to forewarn the Agri¬ 
culturist^ of the approaching insect foe, but also to dissipate any groundless fears of 
such a foe that may prevail, when it can be proved that such fears are really groundless. 
In the Practical Entomologist for October, I860, (II., pp. 1-5,) I investigated the 
migration of this Hateful Grasshopper, from the canons (kanyons) of the Rocky Moun¬ 
tains, into the lowlands of Kansas, Nebraska and Western Missouri, which had just 
then taken place. I further stated my belief that the eggs, which had been that 
* See Westwood Introd. II. pp. 321-2 etc., etc. 
f See my Papers Proc. Ent. Soc. Phil., I., pp. 461-2; III., p. 635; VI., p. 277. 
