ORCHARD BARKBEETLES AND PINHOLE BORERS., 15 
one cone-bearing tree. Like the other species considered in this 
paper, it prefers to work in diseased and dying wood, although, 
as has been indicated, healthy trees are sometimes attacked. The 
species is distributed widely in the eastern part of the United States. 
The female beetle (fig. 17, upper and lower 
right) is about one-eighth of an inch in length, 
of a dark-brown color, and has the head hidden 
from above by the projecting front of the thorax. 
The male beetle (see fig. 17, lower left) is only 
about half as large as the females. The adult 
female, when attacking twigs, usually makes her 
entrance at the base of a bud. The burrow (fig. 
18) extends to and around the pith and has a 
number of short side branches running with the 
grain of the wood. Eggs are deposited loosely 
in the burrow and the larve feed on the am- 
brosia fungus which is propagated on the walls. 
The larvee transform to adults within the burrow 
made by the parent beetle and issue from the tree 
through the entrance hole. Small branches are 
killed by these burrows, but when the beetles 
enter large branches or the trunks of trees the 
injury is not serious, and, as has been stated, 
more often than otherwise only unhealthy wood 
is entered. Injuries caused by twig blight and 
by these beetles are sometimes similar in appear- 
ance, but there is no relationship between the 
two troubles, and orchardists should be able to 
distinguish the insect injury from the blight by 
a close examination of the twigs. 
Fic. 18.—Gallery of 
the pear - blight 
beetle in poplar 
twig: Upper figure, 
transverse section ; 
lower figure, longi- 
tudinal section. 
(Marx. ) 
Where remedial measures are called for, the methods recommended 
for use against the other species described herein should be adopted, 
with the additional precaution of cutting out and burning the in- 
fested twigs. 
