, 1877-11-10
Tho Enrih-WOrIM and the EOr-
mutton Of Mould.


paper before the Geological Society, in
which he showed that the formation
and the characters of the socalled veg
etable mould" which forms covering
Several inches in dchth on the surface OF
all productive land. were due, in great
measure, to the constant activity Ot the
common earth worm. These animals
burrow through the soil, taking into
their bodies, MS they 90, earth. from
which to extract the nutri,ive matters
on which they subsist; ana then, com
ing to the surface, deposit the noD.nu-
tritious portions OF the earth in the form
OF little heaps. These heaps, accumu-
latng, produce superficial layer otvery
finely divided mould. which, in the
course Of years, forms stratum several
inches thick, emincntly suitable for the
growth of plants. The work done by u
single worm is naturally very small, but
the inslgnifcancc OF the individual is
quite made up by the immcncc numbers
in which they exist. Mr.. Darwin ad-
duccd Il case in which field well cover
ed with burnt mari and cinders showed
in fifteen Yeas iour-inch layer OF
mould, the mail and Cinders being all
buried in an even layer beneath it. Thus
"the agriculturist nplowing the ground
follows method strictly natural and
he only initiates in n rude manner, with
out being able to bury the pebbles or
to sift the fine from the course soil, the
work which nature is daily performing
by the agency OF the earlh-wotn..'
This most curious case OF the intimate
relations of animals to plants, and Of
both to the processes ofsub-aerlal change
taking place on the carth's surface, has
recently been worked out in great de
tail by Won Hensen, who, strange to say,
does not seem to have heard OF Darwin's
labors, which he confirms and supple
ments. He states that the adult worms
come to the surface OF the earth at night,
and, with their tails in the mouths of
their burrows, survey the country round,
and collect food in the shape of leaves
and twigs. These are heaped up round
the entrance, the leaves being rolled up
separately and partly drawn into the
tube, where they soon become macerated
and partially decomposed, 50 as to form
such savory meat as the worms soul
lOveth.
Won Hensen's observations were con-
Quoted in garden with layer OF mould
nine inches deep, Snd su5soil Of yellow
diluyial sand. The worm.tubes were
not easily traced in the mould, but were
perfectly clear in the sand, running yerti-
cally dOwnwards to debth of from three
to six feet. The tubes were often found
to be lined with stones about the size of
pins head, brought from the surface,
and fruit kernels were also found in
them. But the point OF Chet impor
tance is, that the walls Of the burrows
were found to be beset with little black
masses of a characteristic shape,-the
excrements of the worms. Besides these
fresh inhabited tubes, others were found
in which the cavity was filed with black
earth, the black color bsing ditfCscd into
the surrounding sand, and these again
passed insensibly into mere black stripes,
veins OF mould running in the sandy
subsoil.
In about half of the uninhabited tubes
were found the roots OF plants growing
on the surface; these followed exactly
the direction of the tuble, and gave off
fine root-hairs through the black walls
of the latter. From an extended series
of observations, Won Hensen states that
the roots ofannuals can only penetrate
into the subsoil through channels open
ed out to them by earth-worms, and he
observes that this penetration must be Of
service to the plant, as the. subsoil re-
tains moisture longer than the surface
layer Ofmould.
The contents of the intestines and the
cycretions of worms show great SIM
ilari,y in microscopical and chemical
! characters to vegetable mould