36 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. 
pressed and concave, the hollow being oval and following the out- 
line of the margins; the bottom side or base is flat. The surface is 
rough and sculptured into irregular polygons with from three to six 
sides. The eggs are adhesive, hard, visible to the naked eye, but 
minute, measuring 0.63 by 0.38 mm., and are deposited singly. They 
differ in aspect from those of the peach borer, and also are usually 
lighter in color and not as large and stout. They are rather more 
difficult to find in nature. 
At present the length of the period of incubation is not well known. 
Mr. Quaintance records it as 74 days in the month of September, 
latitude of Washington, D. C. Upon hatching, the little larva 
cuts its way through the anterior end of the egg, leaving quite a 
large exit hole in the egg shell, which retains its shape and place 
until it weathers off. 
The eggs were first observed in nature by Bailey (1879); he found 
a cluster of them on the under surface of loosened plum bark, about 
6 inches above the roots. Usually, however, they are deposited 
singly along the trunk of the tree, being placed in crevices, openings. 
or roughened places. Sometimes a few are placed on the ground or 
high up in the tree on twigs or leaves, but the majority are de- 
posited on the main trunk of the trees. The number deposited by 
a single female is unknown. Moths kept in confinement refuse to 
mate, and the female deposits few eggs or none at all. To determine 
the number resort is therefore made to dissection. Mr. Quaintance 
dissected two fertile females after death, and found 305 perfect eggs 
in one and 296 in the other, in addition to numbers of small unde-~ 
veloped ones. Each moth had deposited a few eggs before dying, 
which were included in the count.’ Dissection of the ovaries of a 
sterile moth yielded but 58 perfect eggs, but there were present — 
many undeveloped ones. Until more dissections are made the evi- 
dence on this point remains inconclusive. 
The larva.—When the larva hatches it is very small, and especially | 
hard to detect with the naked eye because of its dull white color. It | 
is an ordinary caterpillar, bearing the usual setsze and number of pro- | 
legs, and in its earlier stages is almost indistinguishable from the 
young larve of the peach borer. However, after molting once or | 
twice it acquires a different aspect, which together with a more? | 
pinkish and translucent color makes it somewhat more distinct. 
Throughout all its life it remains about the same color—various | 
shades of creamy white—and lives concealed under the bark. The 
following is a description of a full-grown larva, or instar VI: 
Length, 20.5 mm., average. Greatest width, 3.4 mm. Width of head, 1.94 
mm., average. Normal for the family: Body soiled cream color, immaculate, 
with the usual more or less generalized characters. Head yellowish brown, 
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