INDEX.

Abinger, Roman villa at, 178

——— castings from Roman villa, with rounded particles, 253

Acids of humus, action on rocks, 240

Africa, dust from, 235

Air, currents of, worms sensitive to, 28

Amount of earth brought to the surface by worms, 129

Ants, intelligence of, 93

Archiac, D, criticisms on my views, 4

Artemisia, leaves of, not eaten by worms, 33

Ash-tree, petioles of, 79

Beaulieu Abbey, burial of the old pavement, 193

——— castings from, with rounded particles, 255

Beaumont, Élie de, on vegetable mould, 2

——— the rubbish underlying great cities, 178

——— the transport of dust, 237

——— the permanence of mould, 289

——— the permanence of ancient tumuli, 290

Beech-forests, stones not buried under by castings, 144

Bengal, worms of, 123

Bones, crushed, burial of, under castings, 146

Brading, Roman villa at, 199

———, castings from, with rounded particles, 254

Bridgman, Mr., on worms eating leaves of a Phlox, 33

Buckman, on grasses profiting by being rolled, 10

Burial of the remains of ancient buildings by worms, 176

Burrows, depth of, 109

——— direction of, on a slope, 270

——— excavation of, 98

——— lined with black earth, 111

——— lined with leaves, 112

——— mouths of, worms lie motionless near, 15

——— old, their collapse, 118

——— plugged up, 58

——— terminating in a small chamber, often lined with stones or seeds, 114

Calciferous glands, 17, 43

Cannibal worms, 36

Carnagie, Mr., depth of burrows, 114

Castings, acid, 52

——— from Beaulieu, 101

——— tower-like, near Nice, 106

——— ejection of, 116

——— tower-like, from near Calcutta, 123

——— of great size on the Nilgiri Mountains, 126

——— weight of, from a single burrow and from a given area, 160

——— thickness of layer formed from, during a year, 169

——— ejected over ancient buildings, 253

——— flowing down slopes, 261

——— washed away, 272

——— dry, disintegration of, 275

——— blown to leeward, 283

Cells, free, with calcareous matter in the calciferous glands, 47

Cellulose, digestion of, 37

Chalk-formation, surface of, much denuded, 137

Chalk, residue of, forming a superficial deposit, 138

——— fragments of, soon buried and corroded, 139

——— formation of mould over, 297

Chedworth, Roman villa of, 197

Circular trenches near Stonehenge, 287

Claparède, structure of the intestines of worms, 19

——— on the salivary glands of worms, 42

——— on the calciferous glands, 44

——— the pharynx adapted for suction, 56

——— doubts whether earth serves worms as food, 102, 105

——— on the gizzards of worms, 246

Clematis, petioles of, used in plugging up burrows, 58, 77

Cobra-snake, intelligence of, 94

Collapsing of old burrows, 118

Concluding remarks, 305

Concretions of lime in the anterior calciferous glands, 45

——— calcareous, use of, 54

Corals, mud derived from, 256

Corniche Road, disintegrated castings on, 276, 281

Croll, Mr., on denudation, 233

Crowns or ridges on old ploughed fields, 292

Currents of air, worms sensitive to, 28

Dancer, Mr., on the action and number of worms, 146, 159

Deafness of worms, 26

Débris, over the Roman remains at Silchester, 201

Decay of leaves not hastened by the secretion with which they are bathed, 38

Denudation of the land, 230

Depth to which worms burrow, 109

Digaster, 246

Digestion of worms, 37

——— extra-stomachal, 43

Disintegration of rocks, aided by worms, 240

Distribution of worms, 120

Down, amount of earth here brought annually to the surface, 137

Downs near Winchester, valleys in, 301

Dust, distance transported, 235-237

Earth, amount of, brought to the surface by worms, 129

——— amount of, which flows down a given slope, 266

——— swallowed as food, 100

——— weight of, ejected from a single burrow, 160

Eisen, number of species of worms, 9

——— depth of burrows, 110

Ejection of castings, 116

Embankments on hill-sides, 278, 282

Encampments, ancient, 290

Ernst, Dr., on worms at Caracas, 121

Excavation of the burrows, 98

Fabre, M., on the instincts of Sphex, 93

Farrer, Mr. T. H., on the Roman villa at Abinger, 178-188

Fat eaten by worms, 36

Fields formerly ploughed, 292

Fish, Mr., criticisms on my views, 6

Flints, standing vertically in the residue over the chalk, 138

——— acted on externally and internally by atmospheric agencies, 245

Flowing down of castings, 261

Fluid, digestive, of worms, 37

Food of worms, leaves, 35

——— earth, 100

Foster, Michael, on the pancreatic ferment, 37

——— on the acidity of the contents of the intestines, 52

Foundations, deep, of the Roman buildings at Wroxeter, 227

Furrows on old ploughed fields, 292

Galton, Mr., on the number of dead worms, 14

Geikie, Archibald, on Denudation, 233

——— controverts É. de Beaumonts views on Denudation, 289

———, James, controverts Richthofens views, 237

——— on glaciated rocks, 245

Geographical distribution of worms, 120

Gizzards of worms, 246

Glands, calciferous, 17, 43

——— function of, 49

Glen Roy, evidence of rarity of debacles, 260

Haast, Von, on aboriginal instruments in New Zealand found buried, 147

Hearing, sense of, 26

Heat, perception of, 25

Heaths, inhabited by few worms, except where paths cross them, 10

Hensen on the number of worms in gardens, 5

——— on worms not subsisting on earth, 108

——— depth of burrows, 110

——— on number of worms living in a given area, 158

——— on the composition of mould, 238

——— on the amount of humus formed by two worms, 310

Henslow, Prof., on ledges on hill-sides, 278

Hoffmeister, number of species of worms, 9

——— on worms hybernating in company, 34

——— perception of light by worms, 20, 22

——— on the enemies of worms, 62

——— depth of burrows, 110

——— on hybernation of worms, 114

Hooker, Sir J., on ledges of earth on the Himalaya, 278

Humus acids, action of on rocks, 240, 244

Instinct of worms, 35

Intelligence of worms, 35, 64

Intestines of worms, their contents acid, 51

Islands, inhabited by worms, 120

Johnson, Dr. H., on the Roman remains at Wroxeter, 222-228

——— on ammonia in worm-castings, 242

Johnson, S. W., 'How Crops Feed, 242

Joyce, Rev. J. G., on the Roman remains at Silchester, 201

Julien, Mr. A. A., on the composition of peat, 238

——— on the humus acids, 240, 244

Key, Rev. H., on the burial of cinders by worms, 146

King, Dr., on the formation of mould in forests in France, 5

——— on castings near Nice, 106, 117

——— on great castings on the Nilgiri Mountains and in Ceylon, 126

——— weight of castings near Nice, 163

——— on disintegrated castings on the Corniche road, 276, 281

——— on the washing away of the castings on the Nilgiri Mountains, 274

Knole Park, beech-woods, worms absent, 12

Koninck, De, on the disintegration of rocks, 235

Laburnum leaves, 67

Land, denudation of, 230

Lankester, Ray, on the structure of worms, 18

——— on worms from Kerguelen Land, 121

La Plata, dust storms of, 236

Layard, Mr., on the habits of the cobra, 94

Leaves, worms distinguish the taste of different kinds, 32

——— consumed by worms, 35

——— their decay not hastened by the alkaline secretion with which they are bathed, 38

——— decayed, generate acids, 50

——— used in plugging up burrows, 65

——— used to line burrows, 112

Ledges of earth on hill-sides, 278

Léon, F., on the digestive fluid of worms, 38

Light, perception of, by worms, 20

Lime, carbonate, concretions of, 45

Maer Hall, amount of earth brought to surface, 130

Mallett, Mr., on the sinking of the ground under great buildings, 158

Meat, raw, eaten by worms, 36

Mental qualities of worms, 34

Mint, leaves of, only nibbled, 33

Mississippi, drainage area of, 233

Möbius on the habits of a pike, 94

Moniligaster, 246

Morren on worms surviving long immersion, 13

——— on worms lying motionless near mouths of their burrows, 15

Morren on worms eating sugar, 36

——— on the disappearance of the calciferous glands during winter, 48

——— on stones in the gizzards of worms, 247, 249

Mould, thickness of, annually ejected by worms, 169

——— thickness of, over Roman remains at Chedworth, 199

——— nature and thickness of, over the Roman remains at Silchester, 218

——— thickness of, at Wroxeter, 223

——— formation and thickness of, over the chalk, 297

Mountains, worms absent from, 12

Müller, Fritz, on the worms in South Brazil, 121

Nice, castings near, 106

——— disintegrated castings near, 276

Night, worms leave their burrows, 14

Nilgiri Mountains, castings on, 126

Objects strewed on the surface soon buried under castings, 130

Obliteration of old furrows on ploughed land, 292

Odours, degree of sensitiveness to, by worms, 29

Pancreatic secretion, 37

——— not acid, 53

Paper, triangles of, 82

Path, paved, burial of, by worm-castings, 145

Paths inhabited by worms, 10

Pavement, modern, undermined by worms, 192

Pavements, ancient, subsidence of, at Silchester, 212

Peat, formation of, 239

Percolation of earth into the chalk, 297

Perichæta, naturalized near Nice, 106

Perrier, worms surviving long immersion, 13

——— on the calciferous glands, 44

——— on the action of the pharynx, 56

——— on the burrowing power of worms, 99

——— on naturalized worms, 106

——— on worms killed by acetic acid, 159

——— on the gizzards of worms, 246, 249

Petioles of Clematis, 77

——— of the ash, 79

Pharynx, action of, 56

Pike, stupidity of, 94

Pine-leaves used in plugging up burrows, 58, 70

——— lining burrows, 112

Pipes, formation of, in the chalk, 137

Playfair on Denudation, 290

Ploughed fields, old, 292

Plugging up of the burrows, 58

——— use of the process, 62

Prehension, power of, by worms, 56

Qualities, mental, of worms, 34

Ramsay, Mr., on the sinking of a pavement undermined by worms, 192

——— on Denudation, 231

Remains, ancient, buried by worms, 176

Rhododendron leaves, 69

Richthofen on dust deposits in China, 237

Robinia, petioles of, 81

Rocks, disintegration of, aided by worms, 240

——— triturated in the gizzards of worms, 249

Rolling down of dry castings, 275

Romanes, Mr., on the intelligence of animals, 95

Sachs on living roots corroding rocks, 243

Sage, leaves of, not eaten by worms, 33

Saliva, doubtful whether any secreted by worms, 42

Saussure, H. De, on brick-pebbles, 254

Schmulewitsch on the digestion of cellulose, 37

Scott, Mr. J., on worms near Calcutta, 123

Seeds preserved in the burrows of worms, 115

Semper on various animals swallowing sand, 102

Senses of worms, 19

Silchester, old Roman town, 201

Silica, colloid, acted on by the humus acids, 242

Sinking of the pavements at Silchester, 212

Sites inhabited by worms, 9

Smell, sense of, 29

Social feelings of worms, 34

Sorby, Mr., on the trituration of small particles of rock, 257

Starch eaten by worms, 36

——— digestion of the granules in the cells of leaves, 41

St. Catherine's Hill, near Winchester, 302

Stones, great, undermined by worms at Leith Hill and at Stonehenge, 148

——— small, heaped over burrows, 60

——— small, in the gizzards of worms, 247

——— rounded in the gizzards of worms, 249

Stonehenge, great stones of, undermined by worms, 154

——— circular trenches near, 287

Structure of worms, 16

Subsidence of the pavements at Silchester, 212

Suction, power of, 56

Sugar eaten by worms, 36

Summary of whole book, 305

Surface, objects strewed on, buried under castings, 130

Taste, power of, 32

Thickness of the layer of mould annually ejected by worms, 169

——— of the mould over the remains at Chedworth, 199

——— of the mould over the remains at Silchester, 218

——— of the mould over the Roman remains at Wroxeter, 223

Thyme, leaves of, not eaten by worms, 33

Touch, worms highly sensitive to, 28

Triangles of paper, 82

Trituration of particles of rock in the gizzards of worms, 249

Tumuli, ancient, 290

Tylor, Mr. A., on Denudation, 233

Tylor, Mr. E., on anciently ploughed land, 293

Typhosolis, 19

Utricularia, bladders of, 109

Vibrations, worms sensitive to, 27

Vision, power of, in worms, 20

Walls, ancient, at Abinger, penetrated by worms, 188

——— penetrated by worms at Silchester, 209

Washing away of castings, 272

Wedgwood, Mr., on the formation of mould, 3

Weight of earth ejected from a single burrow, 160

Whitaker, Mr., on Denudation, 232

White, on worms leaving their burrows at night, 14

Winchester, chalk formation near, 301

Wind, action of, on castings, 283

Worms, nocturnal, 13

——— large numbers occasionally die, 14

——— dead eaten by other worms, 36

Worms, contents of intestines, acid, 51

——— their castings, acid, 52

——— power of suction, 56

——— plugging up their burrows, 58

——— intelligence of, 64

——— formation of their burrows, 98

——— number of, living in a given area, 158

——— penetrating ancient walls, 188, 209

——— gizzards of, and the trituration of the containe stones, 246

——— prefer to live in fine earth, 291

Wright, Mr., on the age of Wroxeter, 221

Wroxeter, old Roman town of, 221