716 
ANNUAL REPORT OF NEW-YORK 
PINE. TRUNK. 
•also a stout spine; the antennae only reaching the base of the 
wing covers, which are dull yellowish gray variegated with 
black, each with three elevated lines, the outer two uniting at 
their tips. See Harris’s Treatise, page 102. 
242 . Wood-engraver bark-beetle, Tbmicus xylographus, Say. (Colcoptora. 
Scolytidie.) 
In the outer surface of the sap wood and inner layers of the 
bark, mining a long slender thread-like track, usually straight, 
lengthwise, four to eight inches long, from which numerous 
smaller short tracks branch off mostly at right angles; a small 
bark-beetle 0.12 long, which comes abroad mostly in May, of a 
chestnut color, the declivity at the tip of its wing covers having 
four or five minute projecting teeth upon each side. 
This, like the other bark beetles, has a compact cylindrical 
body at least three times as long as broad, with the thorax 
forming almost half of the entire length and having the head 
deeply sunk in its anterior end and almost hid. Their antenna? 
are quite small and are composed of a long basal joint which 
becomes thicker towards its tip and is followed by five very 
small joints surmounted by a large round flattened club which 
is divided by sutures into three or four segments. 
This species is glossy and beurded with fine hairs. Its thorax is shagrecned 
anteriorly with minute elevated points which farther back become less dense, 
and the basal half is covered with fine punctures, with a smooth line above 
along the middle from the centre backwards. The wing covers have rows of 
coarse punctures and minute ones on the interstices between these rows, and 
their tips are abruptly declined as though cut or gnawed off, the outer margin 
of this declivity having four or five small projecting teeth upon each side, ft 
is usually chestnut colored, with the antenna: and legs paler, but individuals 
may be met with of the following varieties: 
Variety a, nigricollis. Thorax black. 
b, niger. Thorax and wing covers black. 
z,Julvus. Thorax and wing covers pale yellowish. 
The wood-engraver bark-beetle is the most common and pro¬ 
bably the most pernicious of all the insects infesting the forests 
of white pine in the State of New-York, and of yellow pine ( P. 
varialilis ) in the states south of us; and we are surprised that 
no notice of this important depredator is contained m Hr. Har- 
