of them were infested with the
same beetles, though the excavations had not as yet been sufficiently
extensive to affect the outward appearance of the bush. They must all
die during the coming winter, and next spring will show that, in Lewis
County alone, hundreds of thousands of young sugar maples perished
from the ravages of this Scolytid during the summer of 1882.
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.
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