236 
THE STUD Y OF INSECTS 
Fig. 282. 
The case made by certain of the leaf-eating species is 
very characteristic in form (Fig. 282), being strongly taper¬ 
ing and much curved ; in this instance the 
case is composed largely of the excrement of 
the larva. 
The Indian-meal Moth, Plodia interpunc - 
tella (Plo'di-a in-ter-punc-tel'la) is the best 
known of the species that infest stored 
provisions. The larva is the small whitish 
worm, with a brownish-yellow head, that 
spins thin silken tubes through meal or among 
yeast-cakes, or in bags or boxes of dried fruits. The moth 
expands about five eighths of an inch. The basal two fifths 
of the fore wing is dull white or cream-colored ; the outer 
part reddish brown, with irregular bands of blackish scales. 
The Mediterranean Flour-moth, Ephestia kiihniella 
(E-phes'ti-a kiihn-i-el'la), is an even more serious pest than 
the preceding species, which it resembles in habits. It has 
become very troublesome in recent years in flouring-mills. 
The moth expands about one inch, and is grayish in color. 
Although it is called the Mediterranean Flour-moth, its 
source is not definitely known. Nor do we know of any 
easy way of ridding an infested mill of it. Carbon bisul¬ 
phide is perhaps the most available insecticide in this 
case. 
Zimmermann’s Pine-pest, Pinipestis zinvmermanni (Pin-i- 
pes'tis zim-mer-man'ni), is a common species, the larva of 
which is a borer. It infests the trunks of pine, causing large 
masses of gum to exude. The moths appear in mid¬ 
summer. 
The Coccid-eating Pyralid, Laztilia coccidivora (Lse-til'i-a 
coc-ci-div'o-ra), differs from the other members of this 
family in being predaceous. It feeds on the eggs and 
young of various scale-insects ( Pulvinaria , Dactylopius , and 
Lecanium ). Figure 283 represents the different stages of 
this insect enlarged, and the moths natural size resting on 
