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nionly found on the trunk and roots in .summer are the wingless, 
agamic females. They give birth to living young, and continue to do 
so, possibly for several years. In spring some of the root-lice will 
crawl up the trunk and continue to breed there till fall. The colonies 
of lice on the trunk give rise to winged and migratory females. These, 
when they locate, give birth to wingless male and female lice, and each 
female deposits a single winter egg in a crevice of the bark. This egg 
will, in the spring, hatch into a female which will start a new colony 
of wingless lice on the trunk. Some of these will, in the summer, 
crawl down upon the roots and continue to breed there. In the north 
the colonies on the trunk are apt to be killed out by the severe cold 
weather, but in warmer latitudes many of them live through the winter, 
particularly if they are protected by a piece of bark. 
THE BLACK PEACH APHIS. 
(Aphis persicse-niger E. F. Smith — fig. 16.) 
This insect, like the woolly apple aphis, does its great injury under- 
ground. Its ravages on the roots of peach give a sickly appearance to 
the foliage of the affected tree, the leaves often being light green or 
Fig. 16.— Aphis persicse-niger; winged specimen. (J. B. Smith.) 
yellowish in color, and their edges somewhat rolled. The wingless 
lice on the roots are of a dark-brown color. They breed there con- 
tinuously without producing males or eggs. Early in the spring some 
of the root-lice crawl up the trunk of the tree and locate on the young 
twigs. Here the winged form develops and migrates to other trees- to 
found other colonies. The winged insect is of a shining black or very 
dark brown color, the tibiae of the legs being mostly yellowish. 
