62
BRITISH ANNELIDS.
The girdle or clitellum covers six segments, viz.: the 32nd to the
37th. If the undersurface of the worm is examined carefully along
the girdle, it will be found that a band stretches across segments 33,
34, 35, 36, thus covering the four innermost segments. This band
forms what is known as the tubercula pubertatis. In every genuine
Lumbricus we find the same arrangement, viz.: six girdle segments,
on four of which, omitting the two outermost, the tubercular tubernatis
are situated. One or two species of Allolobophora present a similar
arrangement, but they differ in other respects from the true Lumbricus.
If the 15th segment be examined laterally or sideways, a pouch
will be seen. Here we have the male pore, made conspicuous by
being seated on papilla;. The other two species are without these
cushions or papillae; but the new species to which I have referred
corresponds in this respect with the common earthworm. The setae
or bristles are found in four pairs, and on a few of the segments we
find bristles of a different shape and size. These appear to be of
service to the animal when it has reached the stage of sexual activity.
When we come to deal with the genus Allolobophora, we shall be
able to indicate the means by which to distinguish the earthworm
from those species which have hitherto been so fruitful a source of
trouble. I shall present the distinguishing characteristics of the three
species now under review in tabular form at the end of this paper, so
that a fuller discussion of L. terrestris will not now be necessary. I
retain the old Linnean term, because it is not only the oldest, but the
best. Most of the modern synonyms have been applied to the
worm through want of a perfect knowledge of the species, and it is
found that all the species with which the true earthworm was formerly
confused now fall into the new genus, thus leaving the true earthworm
to enjoy its proper title without dispute.
2. The red worm (L. rubellus) is usually a good deal smaller than
the former. True, it varies greatly in size, and I have found a large
red worm which exceeded an average earthworm. This, however, is
the exception, and the red worm averages three to four inches in
length. It is frequently somewhat darker in colour than L. terrestris,
and the girdle, which is usually a warm brick red, is prominent and
closely fused in the adult. It is a very active worm, and may be
found abundantly in damp pastures, or under stones by running water.
If the turf of a meadow be shaken briskly with a garden fork or other
tool, the worms will dash out of the ground with great alacrity, and it
is pretty certain that among the specimens thus taken it will be pos-