49 
dust lodge in the forks of the tree or branches, and in the loose bark 
on the trunk and around its base. Badly infested trees show a 
dwarfed, faded, or sickly foliage about the middle of May, and 
many of the leaf buds fail to open. The author of this injury is 
a whitish, thick-bodied, distinctly segmented, seemingly footless 
grub, nearly an inch long when full grown, with small head, and only 
a pair of minute feet on the next segment behind. It hatches from 
eggs laid in crevices of the bark from August to October. The 
young borers are still very small when the winter overtakes them, 
and they hibernate in small cavities made by them in the outer bark 
of the trunk and branches. They commence operations when the sap 
of the tree begins to flow the following spring, and presently pene- 
trate the wood, burrowing actively about until July or August, in 
central Illinois, when they begin to change to the pupa (Fig. 54), 
to emerge about a month later in the beetle stage (Fig. 55). 
Fig. 55. Locust Borer, Cyllene robinice: a, male; 6. female, 
indicated. (U. S. Dept. of Agriculture.) 
Enlarged as 
The adult is a very showy, elongate, brown beetle, five-eighths to 
three-fourths of an inch in length, conspicuously marked with three 
straight bands of bright yellow across the thorax and five broken or 
irregular bands of the same color across the wing-covers. There is 
also a bright yellow patch on the upper side of the tip of the ab- 
domen. The beetles are to be found in September, and occasionally 
in early October, on locust-trees, and on various species of golden- 
rod, upon the flowers of which they feed. Now and then a speci- 
