724 
ANNUAL REPORT OF NEW-YORK 
PINE. TRUNK. 
245 . Little bark-beetle, Tomicus pusillus, Harris. 
Under the bark of small sapling pines, mining exceedingly 
fine slender wavy burrows running in every direction; a cylin¬ 
drical chestnut brown bark-beetle much smaller than any of our 
other species, measuring only 0.06 in length, its surface shining 
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 ele¬ 
vated points, the middle of the outer edge of the wing covers 
showing 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 
punctures, 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 T. ramulorum of Perris, 
which mines the small twigs of European pines, but it is evi¬ 
dently a distinct species. It was described by Dr. Harris in 
the Transactions of the Natural History Society of Hartford, 
Conn., vol. i, p. 82, from a specimen imperfectly displayed, 
which he met with in the collection of Mr. Halsey, 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 by a knot-like appearance 
towards the lower part of the following figure on the right side. 
This cavity is appropriately termed the nuptial chamber by 
French and German writers. From it there are usually four 
galleries leading off in opposite directions and running obliquely 
