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i ; et ore 
170 _ INSECTS INJURIOUS TO FOREST AND SHADE TREES. 
= ¢ 
ing beyond the cox of the first legs. It is larger, more bulky than the 
adult. Length, 0.22 inch. 4 
The beetle (Fig. 76) is cylindrical, with the head and prothorax together 
three-fourths as long as the rest of the body; end of the abdomen sud- 
denly truncated, slanting, forming a scoop, the declivity smooth, con- 
cave, and bounded by high walls, which are four-toothed on each side, 
the third from the top the largest. On each wing-cover are eight lines 
of fine, raised tubercles; prothorax with concentric rows of fine tuber- 
cles, but smooth on the posterior third. Seen from beneath, the wing- 
covers project well beyond the end of the abdomen. Color, pale tan- 
brown, a little paler on the thorax than on the wing-covers. Body 
eovered with stiff, dense hairs. Length, 0.20 inch. 
34. THE LITTLE BARK-BEETLE. 
Pityophthorus puberulus Leconte.* 
Under the bark of small sapling pines, mining exceedingly fine slender wavy bur- 
rows running in every direction: a cylindrical chestnnt-brown bark-beetle much 
smaller than any of our other species, measuring only 0.05 in length, its surface shin- 
ing and pierced with small deep punctures which on the wing-covers are placed in 
close rows, the thorax but half as long as the wing-covers and rough anteriorly from 
dense minute elevated points, the middle of the outer edge of the wing-covers show- 
ing a slight concavity, the declivity at their tips with a moderate excavation formed 
by a smooth longitudinal groove upon each side of the suture, the suture itself being 
elevated and having on each side of it an impressed line in which are minute punct- 
ures, the outer margin of the declivity with numerous fine bristles, but without any 
projecting teeth, and the tips of the wing-covers drawn out into a very small acute 
point. 
This beetle very closely resembles the 7. ramulorum of Perris, which 
mines the small twigs of European pines, but it is evidently a distinet 
species. It was described by Dr. Harris in the Transactions of the Nat- 
ural History Society of Hartford, Conn., vol. i, p. $2, from a specimen 
imperfectly displayed, which he met with in the collection of Mr. Hal- 
sey, but he had no knowledge of its habits. And this I believe is the 
only notice of this insect which has hitherto appeared. Its minute size 
has probably caused it to be overlooked by collectors, although it is so 
common that the bark of dead young pines which are two inches in 
diameter or less can seldom be broken away without coming upon its 
tracks, with some of the dead insects in them. Its tracks are readily 
distinguished from those of other species by their extreme slenderness, 
and being packed with fine white sawdust they resemble a tangled mass 
of small threads lying upon the surface of the wood. On coming to 
inspect them particularly, small irregular cavities will be noticed, one of 
which is represented bya knot-like appearance. This cavity is appropri- 
ately termed the nuptial chamber by French and German writers. From it 
* Leconte states that this is not the Tomicus pusillus of Harris, as Fitch supposed, 
“but is quite different, and is closely allied to T. ramulorum Perris, which is consid- 
ered by Eichhoff as the same with typographus Ratzburg.” Leconte adds in a letter 
that this is most probably P. puberulus - 
