tile, which had been strewed on the surface of the soil, were stuck into
the interstices between the pine-leaves; and these interstices were
likewise plastered with the viscid castings voided by the worms. The
structures thus formed cohered so well, that I succeeded in removing one
with only a little earth adhering to it. It consisted of a slightly
curved cylindrical case, the interior of which could be seen through
holes in the sides and at either end. The pine-leaves had all been drawn
in by their bases; and the sharp points of the needles had been pressed
into the lining of voided earth. Had this not been effectually done, the
sharp points would have prevented the retreat of the worms into their
burrows; and these structures would have resembled traps armed with
converging points of wire, rendering the ingress of an animal easy and
its egress difficult or impossible. The skill shown by these worms is
noteworthy and is the more remarkable, as the Scotch pine is not a native
of this district.
After having examined these burrows made by worms in confinement, I
looked at those in a flower-bed near some Scotch pines. These had all
been plugged up in the ordinary manner with the leaves of this tree,
drawn in for a length of from 1 to 11 2 inch; but the mouths of many of
them were likewise lined with them, mingled with fragments of other kinds
of leaves, drawn in to a depth of 4 or 5 inches. Worms often remain, as
formerly stated, for a long time close to the mouths of their burrows,
apparently for warmth; and the basket-like structures formed of leaves
would keep their bodies from coming into close contact with the cold damp
earth. That they habitually rested on the pine-leaves, was rendered
probable by their clean and almost polished surfaces.
The burrows which run far down into the ground, generally, or at least
often, terminate in a little enlargement or chamber. Here, according to
Hoffmeister, one or several worms pass the winter rolled up into a ball.
Mr. Lindsay Carnagie informed me (1838) that he had examined many burrows
over a stone-quarry in Scotland, where the overlying boulder-clay and
mould had recently been cleared away, and a little vertical cliff thus
left. In several cases the same burrow was a little enlarged at two or
three points one beneath the other; and all the burrows terminated in a
rather large chamber, at a depth of 7 or 8 feet from the surface. These
chambers contained many small sharp bits of stone and husks of
flax-seeds. They must also have contained living seeds, for on the
following spring Mr. Carnagie saw grass-plants sprouting out of some of
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