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Nature of the sites inhabited-Can live long under
water-Nocturnal-Wander about at night-Often
lie close to the mouths of their burrows, and are
thus destroyed in large numbers by birds-Structure
-Do not possess eyes, but can distinguish between
light and darkness --Retreat rapidly when brightly
illuminated, not by a reflex action-Power of atten-
tion-Sensitive to heat and cold-Completely deaf
-Sensitive to vibrations and to touch--Feeble
power of smell-Taste-Mental qualities-Naturo
of food-Omnivorous-Digestion-Leaves before
being swallowed, moistened with a fluid of the
nature of the pancreatic secretion-Extra-stomachal
digestion - Calciferous glands, structure of Cal-
careous concretions formed in the anterior pair of
glands-The calcareous matter primarily an excre-
tion, but secondarily serves to neutralise the acids
generated during the digestive process 8-54
CHAPTER II.
HABITS OF WORMS-continued.
Manner in which worms seize objects-Their power
suction-The instinct of plugging up the mouths of
their burrows-Stones piled over the burrows—
The advantages thus gained-Intelligence shown by
worms in their manner of plugging up their burrows
-Various kinds of leaves and other objects thus
used-Triangles of paper-Summary of reasons for
believing that worms exhibit some intelligence—
Means by which they excavate their burrows, by
pushing away the earth and swallowing it-Earth
also swallowed for the nutritious matter which it
contains-Depth to which worms burrow, and the
construction of their brows--Burrows lined with
castings, and in the upper part with leaves--The
lowest part paved with little stones or seeds-
Manner in which the castings are ejected-The
collapse of old burrows-Distribution of worms-
Tower-like castings in Bengal-Gigantic castings
on the Nilgiri Mountains-Castings ejected in all
countries Page 55-128
CHAPTER III.
THE AMOUNT OF FINE EARTH BROUGHT UP BY WORMS
TO THE SURFACE.
Rate at which various objects strewed on the surface of
grass-fields are covered up by the castings of worms
-The burial of a paved path-The slow subsidence
of great stones left on the surface-The number of
worms which live within a given space-The
weight of earth ejected from a burrow, az 3 from til
the burrows within a given space-The thub
of the layer of mould which the castings
a
space would form within a given time if f
spread out—The slow rate at which would ca increase to a great th ckness-Conclusi n
CHAPTER IV.
Page 120-170
THE PART WHICH WORMS HAVE PLAYE" IS TE
BURIAL OF ANCIENT BUILLIN »8.
The accumulation of rubbish on the sites of great dide
independent of the action of wrus-Te bari of
a Roman villa at Abinger-The floors and walle
penetrated by worms-Subsidence of a modern
pavement—The buried pavement at Beaulien Abbey
-Roman villas at Chedworth and Brading-The
remains of the Roman town at Silchester-The
nature of the débris by which the remains are
covered- The penetration of the tesselated fors
and walls by worms-Subsidence of the floors-
Thickness of the mould-The old Roman city of
Wroxeter-Thickness of the mould-Depth of the
foundations of some of the buildings Conclusion
176-229
CHAPTER V.
THE ACTION OF WORMS IN THE DENUDATION OF
THE LAND.
Evilence of the amount of denudation which the land
has undergone-Subaerial denudation-The deposi
tion of dust-Vegetable mould, its dark colour and
fine texture largely due to the action of worms—
The disintegration of rocks by the humus-acids→→
Similar acids apparently generated within the
bodies of worms-The action of these acids facilitated
by the continued movement of the particles of earth
-A thick bed of mould checks the disintegration
of the underlying soil and rocks-Particles of stone
worn or triturated in the gizzards of worms-
Swallowed stones serve as millstones-The levigated
state of the castings-Fragments of brick in the
castings over ancient buildings well rounded.
triturating power of worms not quite insignificant
under a geological point of view Page 230-258
The
CHAPTER VI.
THE DENUDATION OF THE LAND-continued.
Denudation aided by recently ejected castings flowing
down inclined grass-covered surfaces-The amount
of earth which annually flows downwards—The
effect of tropical rain on worm castings-The finest
particles of earth washed completely away from
castings-The disintegration of dried castings into
pellets, and their rolling down inclined surfaces--
The formation of little ledges on hill-sides, in part
due to the accumulation of disintegrated castings-
Castings blown to leeward over level land---An
attempt to estimate the amount thus blown-The
degradation of ancient encampments and tumuli—
The preservation of the crowns and furrows on land
anciently ploughed-The formation and amount of
mould over the Chalk formation
259-304