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tor shelter and for other food, including such substances as the 
dirt in the cracks of the floors, bits of broken grain, dead insects, 
insect castings, molds, cobwebs, and cloth; or they may feed occa¬ 
sionally on grain alone. Many of these insects are introduced 
species, of cosmopolitan range, and are scattered abroad in ship¬ 
ments of stored grain and other products. 
GRANARY MOTHS 
The Angoumois Grain Moth 
(Sitotroga cevealella 01 .) 
A characteristic example of the work of this insect is an ear of 
corn peppered with small round holes, often two or three to a single 
kernel (Fig. i). These are produced by a caterpillar which has 
eaten out the embryo and the other soft parts of the seed and has 
then cut through the top of the grain a small round hole which it 
has covered with a web. In the cavity within the kernel it changes 
to the moth, and then, breaking thru the delicate silk cover closing 
its burrow, it makes its way to freedom and takes flight. 
Fig. 2. Angoumois Grain INJotli. Sitotroga ccrcalclla: a. imago (XaG G pupa 
(X 13 ) ; c, grain of corn with a portion of surface removed to 
show injury (X 3 ^), 
