i. 29, 30

combustion a case of impetus, i. 30

Comets, spectra of, i. 159 _note_, 163

Conferva glomerata, development of, i. 207

Confervaceæ, habitat of, i. 206, 207 structure and development of, i. 207 reproduction of, i. 208 modes of action of the vital forces of, i. 210

Confervæ, cells and development of, i. 171

Confervæ, marine, structure, habitat, and reproduction of, i. 221, 222.

Conidium, or spore-dust cell, of fungi, i. 279

Coniomycetes, characters of the family of, i. 275

Conjugatæ, structure of the genus, i. 216

Conjugation, propagation of diatoms by, i. 200, 204

Constantinea rosa marina, i. 235

Constantinea sitchensis, i. 235

Copepoda, characters of the, ii. 204

Copper, properties of, i. 4 colour of, in reflected and absorbed light, i. 35, 36 its power of transmitting electricity, i. 90 atomic weight of, compared with that of hydrogen, i. 100 spectra of copper and its compounds, i. 145, 146

Copper, peroxide of, combination forming, i. 104

Coral, structure of the coral polypes, ii. 133, 134 composition of the stony substance of, ii. 137 reef-building corals, ii. 138 red, ii. 125 white, ii. 127

Corallina officinalis, mode of reproduction of, i. 230 structure and development of, i. 240

Corallines, structure and mode of propagation of, i. 240

Corallium Johnstoni, structure and habitat of, ii. 127

Corallium rubrum, structure and mode of reproduction of, ii. 125, 126, 127 coral fishing in the Mediterranean, ii. 126

Corallium secundum, structure of, ii. 127

Cordyceps miliaris, characters of, i. 283, 293

Cordyceps purpurea, the second form of ergot, i. 293 structure of, i. 293

Cordyceps Robertsii, form of, i. 293

Coremium glaucum, production of, i. 287

Corolla of flowering plants, i. 378

Corundum, i. 4

Corynidæ, characters of the family, ii. 90

Cosmarium, structure and development of, i. 194

Cotton, dyes for, i. 125 necessity for mordants for fixing cotton dyes, i. 125 enormous manufacture of cotton in Britain, i. 125

Cowries, shells of, ii. 234, 235

Cow-tree, beverage obtained from the, i. 426

Crabs, structure and mode of reproduction of, ii. 189-197 hermit, structure of, ii. 197 king, fossil, ii. 211 spider, structure of, ii. 211

Creosote, i. 121 its property of preventing the decay of organic matter, i. 121

Cressylic acid, how produced, i. 120, 121 chemical composition of, i. 128

Cristallaria compressa, form of, ii. 28 structure of, ii. 39

Cristata, siliceous skeleton of, ii. 60

Crocus, structure and mode of reproduction of, i. 387, 388

Cruoria pellita, tetraspores of, i. 237

Crustacea, characters of the, ii. 188 fossil crustacea, ii. 211

Crustacea, Decapod. _See_ Decapods

Cryptogamia, spores of, i. 177, 178

Cryptonemiaceæ, multitude of forms of, i. 234 structure of, i. 234

Crystal, rock, its transmission of chemical solar rays, i. 65 absorption of invisible rays by, i. 65 change of position of the optical axes of the crystals of, by heat, i. 73

Crystallization, relation of polarization of light and heat to crystallization, i. 70, 71 axes of symmetry of crystals, i. 71, 72 change of position of the optical axes of crystals by heat, i. 72 effect of pressure on the optical axes of crystals, i. 73 influence on the aggregation of, i. 73, 74 probable origin of the crystalline form, i. 74 causes of the variety of forms assumed by matter, i. 74 deviation of dimorphous crystals from the general law of crystallization, i. 75 proof of the connection between the magnetic forces and crystalline structure, i. 76 conditions of the position which crystals take with regard to the magnetic force, i. 76

Crystalloids, or crystalline substances, diffusibility of, i. 109

Crystals, water an essential element in, i. 107 alterations in crystals by heat, i. 108

Cunina octonaria, larvæ of, parasites of the Turritopsis nutricula, ii. 100

Cusconine, structure of, and whence obtained, i. 427

Cuthbert’s, St., beads, ii. 175

Cutaneous diseases caused by fungi, i. 274

Cutleria multifida, structure, mode of reproduction, and habitat of, i. 248

Cuttle fish, structure of the, ii. 245-247

Cyanogen, combines with other substances and simple atoms, as if it were a simple element, i. 106 combination forming it, i. 106

Cyathea medullaris, used as food in New Zealand, i. 360

Cyatheæ, structure of, i. 360

Cyatheineæ, characters of the group, i. 344 sporangia of, i. 343 structure and fructification of, i. 360

Cycloclypeus, structure and habitat of, ii. 48

Cyclops quadricornis, structure and mode of reproduction of, ii. 205, 206

Cydippe pileus, structure of, ii. 101, 102

Cymothea, their food and mode of taking it, ii. 203

Cyprææ, or cowries, shells of, ii. 234, 235

Cypris, structure and mode of reproduction of, ii. 207, 208

Cystopteris, characters and habitat of the genus, i. 348, 349

Cystopus candidus, or Uredo candida, structure, habitat, and mode of reproduction of, i. 278

Cystopteris fragilis, or brittle bladder fern, structure and habitat of, i. 349

Cystoseira, structure and habitat of, i. 255

Cystoseireæ, habitat of, i. 255

Cyttaria, the food of the Fuegians, i. 292 habitat of the, i. 292

D

Dactylocalyx pumiceus, spicula and skeleton of, ii. 60

Daphnia pulex, or arborescent water-flea, structure and mode of reproduction of, ii. 208

Dasya, structure of, i. 241, 242

Dasyglœa, structure of, i. 215

Datura sanguinea, intoxicating effect produced by a drink obtained from, i. 427

Davallia canariensis, or hare’s-foot fern, i. 351

Davallieæ, structure and habitat of, i. 350, 351

Dead bodies, agents in the decomposition of our, ii. 67

Decapoda, structure of, ii. 245

Decapods, tribes of the, ii. 188 characters of the, ii. 189

Delesseria alata, structure of, i. 243

Delesseria angustissima, structure of, i. 243

Delesseria sanguinea, structure and habitat of, i. 239

Dematiei, structure of, i. 283

Dendritina elegans, form of, ii. 28 structure of, ii. 32

Dendritine variety of the Peneroplis, characters and habitat of, ii. 32 fossils of, ii. 33

Dennstædtia, indusium of, i. 350

Deparia prolifera, sorus and indusium of, i. 350

Desmidiaceæ, structure and development of, i. 191 _et seq._ their habitat, i. 195

Dextrine, production of in plants, i. 421

Dialysis, as a method of separating and analysing substances, i. 108 what constitutes dialysis, i. 110 Prof. Graham’s instrument for, i. 110 an extraordinary result of, i. 110

Diamagnetism, i. 75

Diamond, i. 13, 15 heat required to consume the, i. 15 crystallisation of the, i. 15 its resistance to electricity, i. 90

Dianthine, production of, i. 127

Diastase, production of, in plants, i. 420

Diatoma vulgare, structure and development of, i. 197

Diatomaceæ, or Brittleworts, found all over the globe, i. 196, 204 variety of forms of, i. 196 structure of, i, 197 development of, i. 200 social plants, i. 205 food for many aquatic animals, i. 205 fossil deposits of shells of, i. 206 enormous geological changes caused by, i. 206

Dicksonia antarctica, structure of, i. 349

Dicksonia lanata, structure of, i. 349

Dicksonia squarrosa, habitat of, i. 349

Dicksonieæ, i. 349 structure of, i. 350

Dicotyledonous, or exogenous, plants, structure and mode of reproduction of, i. 404-428

Dicranei, structure of, i. 329

Dictyopodium trilobum, structure and habitat of, ii. 20

Dictyota, structure of the genus, i. 246

Dictyota dichotoma, structure and mode of reproduction of, i. 247

Dictyoteæ, structure and mode of reproduction of, i. 246

Dictyurus purpurascens, structure of, i. 242

Difflugia, structure and minuteness of the shells of, ii. 22 their architecture, ii. 23

Difflugia pyriformis, structure, and habitat, and mode of propagation of, ii. 22, 23

Diffusibility, most substances differ in, i. 109 partial decomposition of definite chemical compounds by, i. 109 reciprocal diffusion of gases through porous plates, i. 111-113 the diffusing instrument used by Prof. Graham, i. 112

Digestion, chemical powers causing, ii. 4

Dimorphism, contrasted with isomorphism, ii. 99

Diphyidæ, structure and habitat of the, ii. 103

Diplazieæ, characters of the group, i. 352

Diplazium, structure and fructification of, i. 352

Distillation, ordinary, i. 117 destructive, i. 117 of coal, i. 117

Distomata, characters of the, ii. 146

Dracæna Draco, or dragon tree of Teneriffe, i. 387

Drummond’s light, how produced, i. 30 the continuous spectra of, i. 132

Dry rot in wood, cause of, i. 266 on various substances, i. 285

Dulses, red, i. 235

Dumontia filiformis, structure of, i. 235

D’Urvillæa, structure, fructification, and habitat of, i. 256

Dyes obtained from aniline, i. 122-124 vegetable dyes, i. 124 mordants for cotton when dyed, i. 125 effects of electricity and the east wind on the process of dyeing, i. 126 obtained from preparations of petroleum, i. 127 obtained from lichens, i. 303 blue dye obtained from some club mosses, i. 374

E

Ear-shell, structure of the, ii. 234

Earth, quantity of heat which would be generated if it were arrested in its orbit, i. 27 and if it struck the sun, i. 28

Earth light, causes of, i. 68

Earth-worm, structure and food of the, ii. 151, 152

Echinodermata asteroïdea, structure, mode of reproduction, and habitat of, ii. 169-174

Echinodermata crinoïdea, or stone-lilies, structure, habitat, and mode of reproduction of, ii. 175, 176 fossil remains of, ii. 175

Echinodermata Echinoïdea, structure and mode of reproduction of, ii. 177-182

Echinodermata: fossil Echinidæ, ii. 182, 183

Echinodermata Holothuroïdea, structure and mode of reproduction of, ii. 183

Echinodermata Sipunculidæ, characters of, ii. 186, 187

Echinodermata Synaptidæ, characters of the order of, ii. 184, 185

Echinus, structure of, ii. 176, 177

Echinus miliaris, spines of the, ii. 181

Ecklonia, structure and habitat of, i. 252

Ecklonia buccinalis, structure of, i. 250

Ectocarpeæ, form, structure, and habitat of, i. 244, 245

Ectocarpus pulsillus, fruit of, i. 245

Effusion of gases by pressure, i. 109, 110 Prof. Graham’s experiments, i. 113

Electricity, i. 30 permanent and regular current of, over the earth, in the atmosphere and in the surface of the earth, i. 31 thunder and lightning, i. 31 force exerted in the creation of the deep, i. 31 the voltaic battery and the electro-magnetic induction apparatus, i. 31, 32 reciprocity of action of electricity and heat, i. 31 electricity produced by chemical action, and conversely, i. 32 intensity of the light and heat of the electric spark, i. 32 produced by fifty Bunsen elements, i. 32 conducting power of charcoal, i. 32 air and glass non-conductors, i. 32 proof of the correlation of heat and electricity, i. 33 motion of the atoms of a conducting wire during the passage of an electric current, i. 33 effect on a conducting wire of an invariable transit of electricity sent from the same pole of an inductive apparatus, i. 33 difference between electric and magnetic currents, i. 33 influence of electricity on the aggregation of matter, i. 74 ratio between the specific heat and weight of the atoms of matter, i. 74 influence of magnetism on the stratified appearance of the electric light, i. 78 extreme heat and light of electric discharges, i. 84 the arc discharge, i. 84 cause of the stratified discharge, i. 85 effect of varied intensity on electric discharges, i. 86, 87 effect of varied resistance on electric discharges, i. 88, 89 varied facility with which substances transmit electricity, i. 90 illustration of the action of electricity and magnetism on light, i. 90 instances of the correlation of electricity and heat, i. 91 voltaic electricity, and its combination and resolution of substances according to the law of definite proportions, i. 94 Faraday’s law of the quantity of electricity required to separate and unite the same atoms, i. 94 superiority of voltaic over static electricity, i. 95 electricity the most powerful instrument of analysis, i. 95 capacity of atoms for electricity, i. 100 a given quantity of electricity required to separate combined substances into their component parts, i. 101 spectrum analysis of the electric spark, i. 138 development of electricity in plants and flowers, i. 430 electric currents in the nerves and muscles of animals, ii. 7

Electro-chemical action in heterogeneous atoms of matter, i. 95

Electro-magnetic induction apparatus, i. 31 Ruhmkorff’s, i. 32

Elvellacei, characters of the, i. 290

Empusa Muscæ, or fly fungus, i. 274

Encalypta vulgaris, organs of fructification of, i. 326

Encrinites, structure of, ii. 175

Endocarpei, structure and habitat of, i. 310

Endocarpon lacteum, structure and organs of reproduction of, i. 299

Endogenous plants, i. 383-403

Enteromorpha, characters of the genus, i. 223

Enteromorpha intestinalis, structure and habitat of, i. 223, 224

Entomostraca, characters of the, ii. 203

Entophytes, characters of the group of, i. 275, 276 sporangia, or spore-cells, of, i. 279

Entozoa, characters of the order of, ii. 144 transformations of the young of the, ii. 146

Eolis, the crowned, structure of, ii. 240, 241

Eozoön Canadense, may be regarded as the first appearance of animal life upon the earth, ii. 54 found in fundamental quartz rocks, ii. 54 structure of, ii. 55 range of its existence, ii. 56

Epipactis palustris, structure and mode of reproduction of, i. 397, 398

Epiphytes, characters of the group of, i. 275

Epithemia, mode of development of, i. 202

Epizoa, or suctorial crustacea, structure, habitat, and mode of reproduction of, ii. 212

Equisetaceæ, or horse-tails, characters of, i. 367 contrasted with ferns, i. 369 large quantity of silex in, i. 369 size and habitat of fossil and existing species, i. 369

Equisetum giganteum, structure and fructification of, i. 368

Ergot, Cordyceps the second form of, i. 293

Errantia, structure and habitat of the, ii. 156, 157, 161

Erysiphe, mildew formed by, i. 295

Eschara, structure of, ii. 218

Ether, sulphuric absorption of radiant heat by, i. 40

Eucamptodon perichætialis, leaves of, i. 330

Eucyrtidium, structure of, ii. 20

Euglena acus, structure of, ii. 72

Euglena sanguinea, structure of, ii. 72

Euglena, structure of the genus, ii. 72

Euglyphæ, structure and habitat of, ii. 22

Eunice, structure of, ii. 157 mode of reproduction of, ii. 160

Euparmeliaceæ, characters of the group, i. 304

Euphorbiaceæ, or spurgeworts, poisons and food supplied by the, i. 425, 426

Evernia flavicans, colour of, i. 303

Evernia jubata, structure of, i. 302

Evernia vulpina, i. 303 brown dye obtained from, i. 303

Exchange, law of, i. 35 independent proofs of the, i. 35, _note_

Exidia Auricula Judæ, or Jew’s Ear fungus, structure and fructification of, i. 266

Excœcaria Agallocha, poison of the, i. 426

Exogenous plants, i. 404-408

Eyes of man, fungi in, i. 275

F

Fairy rings of the fields, i. 262

Faujasina, structure of, ii. 45

Felspar, fluorescence of, i. 66

Fermentation, fungi producing, i. 286-288 minuteness and lowness of organization of the ferments, ii. 68 habitat of the, ii. 68

Fibrin, formation and structure of, in vegetable organisms, i. 423

Fig, common, juices of fruit of, changed into sugar, i. 426 poison of the white juice of the, i. 426

Filariæ, structure and mode of reproduction of, ii. 147

Filices, or ferns, structure and habitat of, i. 335 range of non-arborescent ferns, i. 335 number of species in North America, Britain, and in other places, i. 336 development of spores, i. 336, 337 roots and stems of, i. 339 leaf-stalks of, i. 340 fronds of, i. 340, 341 structure of tree-ferns, i. 341 fructification of, i. 341 sori, i. 341, 342 sporangia, i. 342, 343 foundation of the systematic arrangement of the ferns, i. 343 annulate and exannulate ferns, i. 344

Film fern, structure and habitat of, i. 362

Fire-damp of coal mines, i. 118

Fireworks, mode of the obtaining of different colours in, i. 132

Fish, phosphorescence of, i. 67

Flowering fern, i. 364

Flowers, absorption of radiant heat by the perfumes of, i. 44 weight of the perfumes, i. 45 chemical combinations forming the perfumes of, i. 97 general structure of flowering plants, i. 378 chemical nature of the colours of, i. 428, 429

Fluorescence, property of, in some solids and liquids, i. 60 Sir D. Brewster’s discovery of, i. 66 Professor Stokes’s examination of the fluorescent spectra of metals, i. 64 employed in tracing substances in impure chemical solutions, i. 67 rapid absorption accompanied by copious fluorescence, and the converse, i. 67 essential difference between fluorescence and phosphorescence, i. 67, 68

Fluorine, i. 18

Fluor spar, i. 18 crystals of, i. 18 acid obtained from, i. 18 fluorescence of, i. 60, 66 absorption of invisible rays by, i. 65 phosphorescence of, i. 66

Flustra, or sea-mat, structure of the, ii. 218

Fly fungus, i. 274

Fontinalei, structure and habitat of, i. 331

Food, miraculous descent of, i. 305 lichens as, i. 305, 308 importance of, to the animal frame, ii. 3

Foot-pound, the, of Mr. Joule, i. 26 unit of mechanical force, i. 26

Foraminifera, structure and geological importance of, ii. 27 various forms of, ii. 28 order of porcellanous foraminifera, ii. 30 order of arenaceous foraminifera, ii. 36 order of vitreous foraminifera, ii. 37 abundance of fossil foraminifera in the sedimentary strata, ii. 52 mode of obtaining casts of, ii. 53 comparison of foraminifera recent and fossil, ii. 53 the Eozoön Canadense, ii. 54 the Carpenteria a link between the foraminifera and sponges, ii. 57

Force, i. 23 store of, eternal and unchangeable, i. 24, 25 cohesion, i. 25 in solids, i. 25 in liquids, i. 25 reciprocal attraction between solids and liquids, i. 25 unit of mechanical force, i. 26 heat generated by impetus, i. 27 unit, or mechanical equivalent of heat, i. 29 combustion a case of impetus, i. 30 energy existing in the coal fields on the globe, i. 30 magnetism and electricity, i. 30 influence of force on the aggregation of matter, i. 73 power of electricity in this respect, i. 74 relations between the force of magnetism and atoms of matter, i. 75 effect of the physical forces on molecular arrangement, i. 91 electricity, i. 91 motion, i. 91 catalysis, i. 91 force of chemical combination, i. 97, 98 relation between chemical affinity and mechanical force, i. 98

Formic acid, synthetical formation of, i. 424

Fragillaria, development of, i. 201

Fraunhofer’s lines, i. 129

Frond, or thallus, of lichens, i. 301 of ferns, i. 340, 341

Fruit, chemical combinations forming the perfumes of, i. 97 preserved, greenish and grey moulds on, i. 285 fungus on decayed, i. 290

Fucaceæ, structure and fructification of, i. 244, 250, 251

Fuci, sexual fructification of, i. 253

Fucoideæ, habitat of some, i. 256

Fucus platycarpus, male and female cells of, i. 253, 254

Fucus vesiculosus, or bladder-wrack, structure and fructification of,