BRITISH ANNELIDS. 171
when it is very difficult, especially with preserved specimens, to
decide whether it is a true Green Worm or not. The male pores are
prominent on segment 15, the girdle begins with the 29th or 30th,
and ends on the 36th or 37th segment. I believe that the normal
number of segments in this genus is eight, but it varies considerably.
On the underside of the girdle we observe three pairs of teats or
pores, situated on segments 31, 33, 35. These are the puberty
pores (tubercula pubertatis). At certain seasons there are also to be
found between these pores and the male pores some small sacs con-
taining life-germs. These are the Spermatophores. If any irritating
substance touches the worm, it pours forth from the openings down
the back, known as the dorsal pores, the characteristic turbid fluid
of which I have already spoken. The dorsal pores commence
between the 4th and 5th segments. Internally the prominent feature
is the three pairs of Spermathecae which stand forth conspicuously
among the other essential organs.
I have received it from Bush Wood and another place on the
eastern side of the forest, through the kindness of Mr. George Day,
F.R.M.S., while Mr. Allen of Canning Town, my most indefatigable
friend and fellow-worker, has sent it from Purfleet, Rainham,
Plaistow (with well-marked variety pallescens, Eisen), Woolwich, and
different parts of Epping Forest.
2. Allolobophora mucosa, Eisen. The Mucous Worm is
not so abundant as A. chlorotica, from which it differs in several
essential particulars. The girdle does not fall near the centre of the
body, but occupies the end of the first third. The tail portion is
therefore about twice as long as the head. The worm is delicate, of
a flesh-colour, semi-transparent when clean, so that the blood vessels
can be well seen, and the course of the haemal fluid observed. The
lip is exceedingly delicate, ramified in every direction with very fine
blood-vessels; the male pores are easily observed, and the girdle is
composed of seven or eight segments, usually beginning on the 26th
and ending on the 32nd. The pores or band (tubercula pubertatis)
cover three consecutive, not alternate, segments, namely 29, 30, 31,
and the dorsal pores commence, as in the Green Worm, between the
fourth and fifth. There is a total of about 100 segments in the body,
the length being, as a rule, three inches or a little more. When irri-
tated the Mucous Worm exudes a fluid which contains a considerable
quantity of white granular matter, which forms a coat around the
body of the worm resembling lime or plaster-of-Paris. There is one
N 2