eik 4 - sa at 7 1 
= ; ‘ ~ ye { j 
ase i INSECTS INJURIOUS TO’ THE: PINE. 163 
| Larva.—It may be readily recognized by having three pairs of long and slender 
- thoracic feet, which are 3-jointed, ending in a long claw, as well as by the broad, flat 
body, the end being broad and rounded. The prothorax is large, transversely oblong, 
not quite so wide, but nearly as long as the three succeeding segments. A pair of 
spiracles on the mesothoracic segment, and the usual ones on the abdominal segments. 
Length, 12™"; breadth, 4™™. Described from one found May 26, at Providence, under 
the bark of the white pine. 
The cell in which the larva rests during the winter, and in which the 
pup and beetles reside, is irregularly oval, about 2 inches long and 
one-third as wide, very shallow, and partly surrounded by a wide border 
of closely packed chips gnawed off from the wood; and partly by the 
excrement or reddish sawdust-like closely packed material, derived 
originally from the inner part of the bark. The entire cavity is thus 
about 4 inches long and 2 wide, and very irregularly oval in outline. 
It seems probable that this larva does not make a regular wavy bur- 
row, but remains in one spot, eating out in all directions from a com- 
paratively fixed point; in this respect it differs from many other Ceram- 
bycid larve. 
31. WOOD-ENGRAVER BARK-BEETLE. 
‘ Xyleborus cylographus Say. 
Order COLEOPTERA; family SCOLYTID#. 
In the outer surface of the sap-wood and inner layers of the bark, mining a long - 
slender thread-like track, usually straight, lengthwise, 4 to 8 inches long, from which 
numerous smaller short tracks branch off mostly at right angles; a small bark-beetle 
8.12 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. 
(Fitch. ) 
This, like 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 antenne 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 bearded with fine hairs. Its thorax is 
shagreened 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 center 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. It is usually chest- 
nut colored, with the antennz 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. 
c, fulvus. Thorax and wing-covers pale yellowish. 
The wood-engraver bark-beetle is the most common and probably the 
