34 TWENTY-EIGHTH REPORT ON THE STATE MUSEUM. 
the winding and branching galleries of a small bark-mining 
beetle, an insect known to entomologists as the Hylurgus 
rufipennis Kirby, though the wings are by no means always 
red, as the name would indicate. Both the mature insect and 
its larvee occurred in countless numbers under the bark of the 
dying and recently dead trees. In a single instance they were 
accompanied by a much smaller beetle of similar shape and 
habits, the Apate rufipennis Kirby,* but the former is evi- 
dently the chief agent in this unprofitable business. These 
insects excavate their passages between the bark and the wood, 
eating away a partofboth. Their extended work is, therefore, 
equivalent to a girdling of the tree. Their numerous galleries 
form an intricate network of furrows on all sides of the trunk, 
and traverse one of the most vital parts of the tree, the newly 
formed and forming layers of wood and bark. The furrows 
are shallow on the surface of the wood, rather more than half 
their diameter being in the bark, but their effect is to interrupt 
the circulation of the nutrient juices, and finally to destroy all 
vital action. The perforations in the bark, by admitting 
moisture, doubtless work more or less injury. The surface of 
the sapwood and the corresponding inner surface of the bark 
of living trees are discolored for a short space on both sides 
of the furrows, as if the injury exerted a poisonous or dead- 
ening influence on the tissues in its immediate vicinity. This 
was clearly seen in a tree which had been but slightly injured, 
there being but few furrows, and these merely longitudinal 
ones without lateral branches. Each occupied the center of a 
discolored stripe about half an inch broad, but which usually 
extended from two to four inches up and down beyond the 
extremities of the furrows. In another tree there were groups 
of furrows separated by considerable intervals, the central 
portions of which intervals had a whitish fresh appearance 
when the bark was first peeled, but after a few moments’ 
exposure to the air the whole surface of the wood had changed 
to a dull, dead brown color, indicating a diseased or unnatu- 
ral condition of the surface tissues. The-foliage on this tree 
had not yet lost the green hue of life, but had commenced fall- 
ing to the ground. 
Small trees are rarely attacked. In the localities visited, 
* I am indebted to Messrs. J..A. Lintner and J. L. Leconte for the entomologi- 
cal names of these insects. 
