Dr. George H Horn, of Philadelphia, to whom I sent specimens for
identification, writes me that the beetle is _Corthylus
punctatissimus_, Zim, and that nothing is known of its habits. I take
pleasure, therefore, in contributing the present account, meager as it
is, of its operations, and have illustrated it with a few rough
sketches that are all of the natural size, excepting those of the
insects themselves, which are magnified about nine diameters.

The hole which constitutes the entrance to the excavation is, without
exception, at or very near the surface of the ground, and is
invariably beneath the layer of dead and decaying leaves that
everywhere covers the soil in our Northern deciduous forests. Each
burrow consists of a primary, more or less horizontal, circular canal,
that passes completely around the bush, but does not perforate into
the entrance hole, for it generally takes a slightly spiral course, so
that when back to the starting point it falls either a little above,
or a little below it--commonly the latter (see Figs. 1 and 2).

[Illustration: FIGS. 1 and 2--Mines of Corthylus
punctatissimus.]

It follows the periphery so closely that the outer layer of growing
wood, separating it from the bark, does not average 0.25 mm. in
thickness, and yet I have never known it to cut entirely through this,
so as to lie in contact with the bark.

From this primary circular excavation issue, at right angles, and
generally in both directions (up and down), a varying number of
straight tubes, parallel to the axis of the plant (see Figs. 1, 2, and
3). They average five or six millimeters in length, and commonly