Introduction

Sir Albert Howard

Author's Introduction to the First Edition

Habits of Worms

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 attention

Sensitive to heat and cold

Completely deaf

Sensitive to vibrations and to touch

Feeble power of smell

Taste

Mental qualities

Nature of food

Omnivorous

Digestion

Leaves before being swallowed, moistened with a fluid of the nature of the pancreatic secretion

Extrastomachal digestion

Calciferous glands, structure of

Calcareous concretions formed in the anterior pair of glands

The calcareous matter primarily an excretion, but secondarily serves to neutralize the acids generated during the digestive process

Habits of Worms

Manner in which worms seize objects

Their power of 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 burrows

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

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, and from all the burrows within a given space

The thickness of the layer of mould which the castings on a given space would from within a given time if uniformly spread out

The slow rate at which mould can increase to a great thickness

Conclusion

The Part Which Worms Have Played in the Burial of Ancient Buildings

The accumulation of rubbish on the sites of great cities independant of the action of worms

The burial of a Roman villa at Abinger

The floors and walls penetrated by worms

Subsidence of a modern pavement

The buried pavement at Beaulieu Abbey

Roman villas at Chedworth and Brading

The remains of the Roman town at Silchester

The nature of the debris by which the remains are covered

The penetration of the tesselated floors 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

The Action of Worms in the Denudation of the Land

Evidence of the amount of denudation which the land has undergone

Sub-aerial denudation

The deposition 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. The triturating power of worms not quite insignificant under a geological point of view

The Denudation of the Land

Denudation aided by recently ejected castings flowing down inclined grass-covered surfaces

The amount of earth which annualluy 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 hillsides, 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 plughed

The formation and amount of mould over the Chalk formation

Conclusion

Summary of the part which worms have played in the history of the world

Their aid in the disintegration of rocks

In the denudation of the land

In the preservation of ancient remains

In the preparation of the soil for the growth of plants

Mental powers of worms

Conclusion

Index