Chapter XV: Section XI: Mollusca (2)

Cellularia ciliata, structure of, ii. 219, 220

Cephalopoda, naked, characters of, ii. 245

Ceramiaceæ, beauty and habitat of, i. 231
characters of the genus, i. 232

Ceramium ciliatum, structure and organs of reproduction of, i. 232

Ceratopteridineæ, or Parkeriaceæ, characters, structure, and habitat of
the group, i. 345, 363

Cerealia, the grasses from whence they were derived unknown, i. 383

Cestum Veneris, structure and mode of reproduction of, ii. 103

Ceterach, characters of the genus, i. 354
structure and mode of reproduction of, i. 354
brought by ocean currents to Europe, i. 355

Ceterach officinarum, or scaly spleen-wort, structure, organs of
fructification, and habitat of, i. 354, 355

Cetraria, or Iceland moss, characters of the genus, i. 304

Cetraria tristis, structure of, i. 304

Ceylon, the black mildew of, i. 297

Chamomile flowers, amount of radiant heat absorbed by the perfume of,
i. 44

Chantarelle, veins of the, i. 264

Characeæ, structure and habitat of, i. 312
fluid currents of, i. 312, 313
reproductive organs of, i. 313

Chara fragilis, structure and mode of reproduction of, i. 314, 315

Charcoal, i. 13
as a conductor of electricity, i. 32

Cheese, blue and brick-red moulds on, i. 285

Cheilanthes odora, scent of, i. 347

Chelidonine, whence obtained, i. 427

Chemistry, laws placing it on a strictly numerical basis, i. 93

Chimneys of bad construction, i. 14

Chiodecton monostichum, structure and habitat of, i. 309

Chiodecton myrticola, habitat of, i. 309

Chirodota, structure and habitat of, ii. 186

Chirodota lævis, wheels of the, ii. 186

Chirodota myriotrochus, wheels of the, ii. 186

Chloride of lime, i. 19

Chlorides, spectra of the, i. 146, 147

Chlorine, i. 18
whence obtained, i. 18, 19
properties of, i. 19, 22
affinity for hydrogen, i. 19, 20
substances produced by the combination of chlorine with oxygen, i. 20
and with nitrogen, and with sulphur, i. 20
Professor Schönbein’s views as to, i. 20, 21
spectrum of, i. 21
absorption of radiant heat by, i. 41, 42
its affinity for iodine, i. 96
atomic weight of, compared with that of hydrogen, i. 100
spectrum analysis of, i. 140

Chlorine gas, substances which take fire spontaneously in, i. 19
combustion of, i. 19

Chlorospermeæ, characters of, i. 180
structure and development of, i. 181

Chondrus crispus, or Carrigeen, structure and mode of propagation of,
i. 235, 236
effect of fresh water on the form of, i. 243

Chorda filum, structure and habitat of, i. 245

Chordaria divaricata, spore cysts of, i. 246

Chordariæ, structure of, i. 245

Chrysophonic acid, whence obtained, i. 303

Chylocladia kaliformis, structure and mode of propagation of, i. 235

Cibotium Barometz, caudex of, i. 350

Cidaris, spines of the, ii. 180

Cinchoneæ, alkaloids obtained from, i. 427

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

Cirripedia, characters of the, ii. 213

Cladocarpi, characters of the group, i. 328

Cladocera, characters of the order, ii. 208

Cladonia, structure of, i. 306

Cladophora, structure of the genus, i. 222

Cladophora pellucida, structure of, i. 222

Claudea, structure of, i. 242

Clavariei, structure and habitat of, i. 266

Clio pyramidata, structure of, ii. 242, 243

Cliona, structure and burrowing apparatus of, ii. 60

Clione borealis, structure and habitat of, ii. 243
fossil remains of, ii. 244

Closterium, double circulation of the internal fluid in, i. 193

Closterium lunula, structure and development of, i. 193

Cloud, force of the chemical combination requisite to form a, i. 98

Cloves, oil of, amount of radiant heat absorbed by the perfume of, i.
44

Club mosses. _See_ Lycopodiaceæ

Coal, i. 13
effect of the consumption of a pound of, in a steam-engine, i. 29, 30
energy in abeyance in the coal existing in the whole globe, i. 30

Coal gas, i. 117, 118
poisonous quality of, i. 118
explosive quality of, i. 118
impurities from which it is freed, i. 118
uses of the black fœtid gas water resulting from the distillation of
coals, i. 119

Coal tar, i. 120
substances produced from, by distillation, i. 120
colours, i. 121, 122

Cobalt, i. 4, 5
crystals of, formed artificially by electricity, i. 74
effect of heat in the magnetism of, i. 77

Coccocarpei, characters of, i. 307

Coccocarpia smaragdina, section of, i. 300

Coccospheres, found at a vast depth in the ocean, ii. 51

Cockle, structure and mode of life of the, ii. 230, 231

Codium, structure and habitat of, i. 219-224

Codium Bursa, structure of, i. 224

Codium tomentosum, structure of, i. 214

Coffee, active principle of, i. 428

Cohesion, properties of, i. 25
in solids, i. 25
in liquids, i. 25

Cohesion: reciprocal attractions between solids and liquids, i. 25
instance of the power of the cohesive force, i. 91

Colchicum, or meadow saffron, mode of reproduction of, i. 388
poisonous alkaloid obtained from, i. 427

Collemacei, structure and habitat of, i. 307

Colloid bodies, i. 109, 110
less diffusible than crystalloids, i. 109
permeable to solutions of crystalloids, but impermeable to solutions
of colloids, i. 110
characteristics of colloids, i. 111

Collomia grandiflora, fructification of, i. 380

Colocasia, water secreted by, i. 430

Colour, causes of, in flowers, green leaves, dyed cloth, gold, and
copper, i. 35, 36

Colouring matter of flowers and plants, i. 428, 429

Comatula, structure of, ii. 175, 176

Combination, chemical, i. 94
the law of definite proportions, i. 94, 95
force of, i. 97, 98

Combustion, effect of, in the consumption of coal in the steam-engine,
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,
i. 252, 253
form of, in the Mediterranean, i. 258

Fuegians, staple food of the, i. 292

Funaria hygrometrica, structure of, i. 324, 327

Fungi, enormous numbers of, i. 260
structure of, i. 260
two principal groups of, i. 260
families of, i. 261, _et seq._
poisonous matter in all, i. 264
luminous, i. 264
stems of, i. 268
spawn of the gelatinous or creamy fungi, i. 269
universality of the lower fungi, i. 273
destruction caused by them, i. 273
parasitic fungi, i. 274
conidium, or spore-dust cell, i. 279
propagation of fungi by fragments of spawn, i. 281
extreme minuteness and profusion of fungi, i. 297
sudden and often disastrous appearance of the lower fungi, i. 297
conditions necessary to the development of fungi, i. 297

Furcellaria fastigiata, mode of reproduction of, i. 229
structure and mode of reproduction of, i. 235, 238

Fusarium tremelloides, its identity with the nettle Peziza, i. 292

G

Galeolaria lutea, structure, development, and mode of reproduction of,
ii. 107, 108

Garancine, from what obtained, i. 124

Gas coal. _See_ Coal gas.

Gases, absorption and radiation of radiant heat by gases and vapours,
i. 38
relation between the density of the gas and the quantity of heat
extinguished or absorbed, i. 40
experiments on coloured gases, i. 40
table showing the absorption of various gases at a common pressure,
or tension of one atmosphere, i. 41
table of absorption for one inch of tension, i. 4
causes of the difference between the absorptive power of compound and
simple gases and vapours, i. 42
radiation equal to absorption, i. 46
action of different thicknesses of the same gas or vapour on radiant
heat, i. 47
dynamic absorption and radiation, i. 49
great opacity of a gas to radiations from the same gas, i. 52
the specific heat of compound gases generally greater than that of
their component elements, i. 101
law of equivalency in weight of, i. 102
diffusion of, i. 111
Prof. Graham’s experiments, i. 112
effusion of, 109, 110, 113
Prof. Graham’s experiments, i. 113
atmolysis, or method of analysing gases, i. 111, 112, 114
internal movement of molecules of matter in a gaseous state, i. 113
coal gas, i. 117
spectrum analysis of, i. 139
oxygen, i. 139
hydrogen, i. 139
nitrogen, i. 140
chlorine, i. 140
bromine, i. 140
iodine, i. 140
superposed spectra of rarefied compound gases, i. 141
researches of M.M. Bunsen and Kirchhoff, i. 141
spectra of the rarefied vapours of:—
sodium, i. 141
iron, i. 142
calcium, i. 142
strontium, i. 142
lithium, i. 142
barium, i. 142
magnesium, i. 142
effect of high temperature on various spectra, i. 142, 143
effects of pressure on various spectra, i. 145

Gasteromycetes, characters of the family, i. 267

Gastropoda, structure of the shells of, ii. 234
structure of the animal, ii. 235
tongue of the, ii. 239

Gelidiaceæ, structure and mode of propagation of, i. 238

Gelidium corneum, structure and mode of propagation of, i. 238
form of, i. 243

Gems, crystals of, formed artificially by electricity, i. 74

Geranium, amount of radiant heat absorbed by the perfume of, i. 44

Glass, a non-conductor of electricity, i. 32
property of, in regard to the transmission of light, i. 36
impervious to chemical solar rays, i. 63

Gleichenineæ, sporangia of, i. 34
structure and habitat of, i. 344, 360

Globigerina bulloïdes, form of, ii. 28

Globigerina, structure of the genus, ii. 40, 41

Globigerinæ, abundance of at vast depths in the ocean, ii. 49-51

Globigerinidæ, characters of the family of, ii. 40

Glycerine, chemical combination forming, i. 97

Glyphidei, characters of the order, i. 309

Glucinum, i. 4

Gold, colour of, in reflected and in absorbed light, i. 35, 36
crystals of, formed artificially by electricity, i. 74

Gonidia, propagation of diatoms by, i. 202, 204
of lichens, i. 300

Goniometer, i. 38

Gorgonia graminea, structure and habitat of, ii. 124, 125

Gorgonia verrucosa, structure, habitat, and mode of reproduction of,
ii. 124

Gorgoniidæ, structure and mode of reproduction of, ii. 123, 124
the three natural groups of, ii. 124

Gracilaria compressa, i. 239

Gracilaria lichenoides, or Ceylon moss, i. 239

Gracilaria armata, mode of reproduction of, i. 230

Graminaceæ, structure and mode of reproduction of, i. 385, 386

Grammatophora serpentina, structure and development of, i. 197

Graphidei, characters of the order, i. 308
habitat of the, i. 309

Graphite, form of the crystals of, i. 15
natural, little or no porosity of, i. 112
porosity of artificial graphite, i. 112

Grasses, silica in the stalks and leaves of the, i. 17

Grasses, structure and mode of reproduction of, i. 385-387

Gravitation, force of, less powerful than that of molecular attraction,
i. 109

Gravity, specific, of atoms, i. 100

Green dye, obtained from the buckthorn, i. 124

Griffithsia, structure, habitat, and organs of reproduction of, i. 233

Grimmiei, structure of the tribe, i. 329

Grinnelia americana, structure and mode of reproduction of, i. 230, 239

Gromia oviformis, structure of, ii. 26, 27

Gromiæ, structure of the genus, ii. 25-27

Guano, mauve dye obtained from, i. 125

Guernsey, richness of the iodine obtained from the sea-weeds of, i. 258

Guinea worm, structure and mode of reproduction of, ii. 147

Gums, formation of, i. 422

Gymnogramma rutæfolia, remarkable distribution of, i. 336

Gyrophora, structure of the genus, i. 308

H

Hairs of plants, structure of, i. 411

Halichondria panicea, mode of propagation of, ii. 60, 61

Haliomma, structure of, ii. 21

Haliotis splendens, or ear-shell, structure of, ii. 234

Haliseris, structure of, i. 247

Halogens, spectra of the, i. 146

Halurus, structure and mode of propagation of, i. 233

Hare’s-foot fern, i. 351

Hart’s-tongue fern, caudex of, i. 340
structure, habitat, and fructification of, i. 351, 352

Heart, and organs representing it in the lower animals, ii. 4

Heat generated by impetus, i. 27
quantity of heat which would be generated if it were arrested in its
orbit, i. 27
probable cause of the heat of the sun, i. 28
effect of the absorption of heat on a body in expansion and
contraction, i. 28
specific heat, i. 28
mechanical equivalent of heat, i. 29
causes of the heat which is the motive force of the steam-engine,
i. 29
reciprocal action of heat and electricity, i. 31
intensity of the heat of the electric spark, i. 32
proof of the correlation of heat and electricity, i. 33
constancy in the amount and refrangibility of the light and heat
absorbed and radiated, i. 34
property of some substances in the transmission of heat, i. 36
substances which transmit radiant heat freely but radiate badly, and
vice versâ, i. 37
Tyndall’s experiments on the radiation and absorption of radiant heat
by gases and vapours, i. 38
relation between the density of the gas and the quantity of heat
extinguished or absorbed, i. 40
absorption of radiant heat by the vapours of volatile liquids, i. 40
Prof. Tyndall’s experiments showing the radiation to be equal to the
absorption of radiant heat, i. 46
action of different thicknesses of the same gas or vapour on radiant
heat, i. 47
dynamic absorption and radiation, i. 49
dynamical evolution of heat, i. 52
experiment illustrating the change of heat into light, i. 62
polarization of heat and light, i. 68, 69
by reflection and refraction, i. 69
effect of heat on the magnetism of iron, nickel, and cobalt, i. 77
extreme heat and light of electric discharges, i. 84
instances of the correlation of electricity and heat, i. 91
capacity of atoms for heat, i. 100
Mr. Croll’s experiments, i. 101
effects of heat on vegetation, i. 169
large amount of heat evolved by vegetables, i. 265
cause of animal heat, ii. 63

Helix, or snail, tentacles of, ii. 236

Helix aspersa, structure of the tongue of, ii. 237

Helix pomatia, teeth of, ii. 237

Hellebore, white, poisonous alkaloid of, i. 427

Helmet shell, structure of, ii. 234

Helminthosporium Hoffmanni, spores of, i. 285, 286

Helminthosporium nodosum, spores of, i. 286.

Helvella, structure and habitat of, i. 291

Hepaticæ, or liverworts, characters of the, i. 316

Hepialus virescens of New Zealand, Cordyceps Robertsii of the, i. 293

Herschel, Sir W., his discovery of invisible rays of light of high
heating power, i. 36

Hewardia, structure of, i. 359

Himanthalia lorea, structure, fructification and habitat of, i. 256

Holly fern, structure of, i. 347

Holothuridæ, or sea-cucumbers, structure and mode of reproduction of,
ii. 183-186

Hop, fungus constituting the mildew of the, i. 295

Hormosiphon arcticus, wide distribution of, i. 212

Hormotrichum, structure of the genus, i. 222

Hormotrichum collabens, structure and mode of reproduction of, i. 222

Hyacinth, structure and mode of reproduction of the, i. 388

Hyalæa, structure of the, ii. 242

Hydra fusca, structure and mode of propagation of, ii. 84, 85

Hydra viridis, structure and mode of propagation of, ii. 85

Hydra vulgaris, structure and mode of propagation of, ii. 85

Hydræ, structure of, ii. 81, 84
mode of propagation of, ii. 84
compound fresh-water Hydræ, ii. 85
development of medusa-buds, ii. 95
alternation of generation of hydræ and medusæ, ii. 96

Hydraulic machine, bog moss acts as a, i. 333

Hydridæ, characters of the group, ii. 81

Hydrobromic acid, amount of absorption of radiant heat by, i. 42

Hydrochloric acid, absorption of radiant heat by, i. 41, 42

Hydrodictyon utriculatum, structure and habitat of, i. 211
reproduction and development of, i. 211

Hydrofluoric acid, i. 18

Hydrogen gas, i. 11
affinity of chlorine for hydrogen, i. 19
absorptive power of, i. 39, 41
proportion of hydrogen to oxygen in the composition of water, i. 94
will not combine with carbon, i. 97
weights of the atoms of, as compared with those of oxygen, i. 99
probable cause of its greater cooling power than that of oxygen, i.
115
one of the illuminants in coal gas, i. 118
spectrum analysis of, i. 139, 144
and of hydrogen, carburetted and attenuated, during and after
decomposition, i. 141
carburetted, one of the illuminants in coal gas, i. 118
marsh-gas and fire-damp, i. 118
peroxide of, i. 9
combination forming, i. 104
combines with other substances and simple atoms as if it were a
simple element, i. 106
sulphuretted, amount of absorption of radiant heat by, i. 41
opacity of, to the invisible rays, i. 65
one of the illuminants in coal gas, i. 118
how freed from coal gas, i. 118

Hydrozoa, campanograde, characters of, ii. 103
ciliograde, characters of the, ii. 101
mode of reproduction of, ii. 103
oceanic, structure of, ii. 81, 86
compound oceanic, structure of, ii. 87
medusiform zooids, ii. 88, 89
mode of reproduction of, ii. 89, 90

Hymenomycetes, family of, i. 261

Hymenophyllum, stem of, i. 339

Hymenophyllum tunbridgense, or film fern, structure and habitat of, i.
362

Hymenophyllum unilaterale, habitat and structure of, i. 362

Hyphomycetes, characters of the family, i. 282

Hypogæi, structure and fructification of the subterranean sub-order of,
i. 267, 268

Hyponitrous acid, combination forming, i. 95

Hypopterygium Smithianum, leaves of, i. 330

I

Ice, absorption of invisible rays by, i. 65
believed to be a colloid body, i. 111

Iceland moss, characters of, i. 304

Iceland spar, polarization of light and heat in, by refraction, i. 69
change of position of the optical axes of the crystals of, by heat,
i. 73

Ileodictyon, eaten as food, i. 268

Impetus, i. 26, 27
heat generated by, i. 27
combustion a case of, i. 30

Indian rubber, dissolved by naphtha for waterproofing, i. 120

Indium, discovery of the metal so called, i. 137
properties of, i. 137

Infusoria, structure, form, and habitat of, ii. 63
abundance of infusoria in the atmosphere, ii. 63, 64
different states of development in one and the same animal, ii. 65
groups of, of opposite characters in the same liquid, ii. 66
the agents in the decomposition of animal matter, ii. 67
minuteness of the ferments, ii. 68
cilia of Infusoria, ii. 68
as organs of locomotion, ii. 69
cell constituting the body of Infusoria, ii. 70
food and organs of digestion of, ii. 70
transparent contractile vesicles, ii. 71
modes of propagation, ii. 74 _et seq._
in a state analogous to hybernation, ii. 78, 79
functions assigned to Infusoria in the economy of nature, ii. 79

Insects, phosphorescence of, i. 167

Intelligence, or the mental principle, of animals, ii. 11, 12

Iodine, i. 18, 21
whence obtained, i. 19
properties of, i. 21, 22
spectrum of, i. 21
atomic weight of, compared with that of hydrogen, i. 100
preparation of, from sea-weeds, i. 128
spectrum analysis of, i. 140, 141
iodine richer at Guernsey than elsewhere, i. 258

Iris germanica, vertical section showing the cellular tissue of, i. 173

Iron heated by percussion or impetus, i. 27
effect of electricity on, i. 32
effect of magnetism of, i. 75, 76, 77
and of heat on the magnetism of, i. 77
feeble affinity of iron for mercury, i. 98
atomic weight of, compared with that of hydrogen, i. 100
spectrum analysis of the rarefied vapour of, i. 142

Isaria, its structure and habitat, i. 282
its destruction of caterpillars, i. 282, 293

Isaria crassa, characters of, i. 283

Isaria farinosa, characters of, i. 283

Isariacei, structure and habitat of, i. 282

Isidæ, structure, habitat, and mode of reproduction of, ii. 125

Isis, structure of the genus, ii. 125

Isomeric substances, i. 104
law of the sequence of three isomeric bodies, and their respective
atomic numbers, i. 105

Isomorphism, property of, in determining atomic weights, i. 99

Isomorphous substances, conduct of, under magnetic influence, i. 76

Isopoda, characters of the order, ii. 202

J

Jam, greenish, and grey moulds on, i. 285

Jungermanniaceæ, or scale mosses, structure, fertilization, and
development of, i. 320-322

Jupiter, the planet, spectrum of, i. 157, 161
constitution of, i. 158

K

Katsup made from the morel, i. 292

Kelp, i. 258
former and present uses of, i. 128

Kerona silurus, structure and food of, ii. 69

L

Labellum of orchids, i. 401

Lactarii, laticiferous vessels of, i. 263

Lady Fern, herbaceous caudex of, i. 340
structure and fructification of, i. 352, 353

Lagenidæ, characters and habitat of the family, ii. 39

Lagoons formed by corals, ii. 140-143

Laminaria bulbosa, structure and fruit of, i. 248

Laminaria debilis, structure of, i. 248

Laminaria digitata, or oar-weed, structure of, i. 249
richness of the iodine obtained from, at Guernsey, i. 258

Laminaria radiata, structure, habitat, and fructification of, i. 250

Laminaria saccharina, or devil’s apron, structure and mode of
reproduction of, i. 249

Laminariæ, submarine forests of, i. 248

Lanosa nivalis, the probable cause of the mildew in rye, i. 297

Lastrea, structure of the genus, i. 346

Lastrea æmula, structure of, i. 346

Lastrea filix-mas, structure of, i. 340

Lastrea rigida, scent of, i. 347

Lastrea Thelypteris or marsh fern, structure of, i. 346

Latex, structure of the, in plants, i. 417

Laughing-gas, or protoxide of nitrogen, combination forming, i. 95

Laurel, oil of, amount of radiant heat absorbed by the perfume of, i.
44

Laurencia dasyphylla, antheridia of, i. 241

Laurencia pinnatifida, or pepper dulse, structure, habitat, and mode of
propagation of, i. 241

Laurencia tenuissima, antheridia of, i. 241

Laurenciaceæ, characters of, i. 240, 241

Laurentian system, ancient formation of the crystallized limestone near
the base of the, ii. 54

Lavender, absorption of radiant heat by the perfume of, i. 44

Lead, its resistance to electricity, i. 90
chloride of, spectrum of, i. 146

Leathesia, structure of, i. 245

Leaves of plants, structure and functions of, i. 410

Lecanora affinis, section of, i. 300
structure and habitat of, i. 305

Lecanora esculenta, habitat of, i. 305

Lecidea, characters of the genus, i. 306

Lecidea geographica, great age of, i. 306

Lecidinei, characters of the order, i. 306

Leeches, structure of, ii. 149-151

Lemon, amount of radiant heat absorbed by the perfume of, i. 44

Lepadidæ, structure of, ii. 213, 215

Lepas anatifera, structure and mode of reproduction of, ii. 215

Lepidodendron, structure of the fossil, i. 375

Lepidostrobus ornatus, structure of, i. 375

Lepraliæ, structure of, ii. 219

Leptopteris, characters of, i. 364

Lessonia, arborescent, forests of, i. 251

Lessonia nigrescens, structure of, i. 251
rings of growth of, i. 252

Leucobryum, structure of, i. 329

Leucobryum glaucum, leaves of, i. 330

Leveillea, structure of, i. 242

Libanea crab, a parasite of the medusæ, ii. 100

Lichens, characters and habitat of, i. 298
two groups of—Gymnocarpei and Angiocarpei, i. 299
horizontal lichens, i. 299
gonidia, i. 300
asci, i. 301
thallus or frond, i. 301
dyes obtained from, i. 124, 303
brilliancy of the colours of, i. 304

Lichina, characters of the genus, i. 310

Lichinei, characters of the group, i. 310

Life, the mystery of, i. 97
instances of individual combined with a common life in the lower
orders of animals, ii. 38

Light, probable cause of the, of the sun, i. 28
Drummond’s light, how produced, i. 30
intensity of the, of the electric spark, i. 32
chemical action of, i. 34
amount of force exerted by the sun’s light within the limits of the
terrestrial atmosphere, i. 34
constancy of the amount and refrangibility of light and heat absorbed
and radiated, i. 34
causes of colour of flowers, leaves, dyed cloth, and gold and copper,
i. 35, 36
property of some substances in the transmission of radiant light and
heat, i. 36
invisible rays of high heating power existing beyond the red end of
the solar spectrum, i. 36
Melloni’s investigation of the laws of radiation and absorption of
radiant heat in solid and liquid matter, i. 38
chemical power of the light of the moon and stars, i. 55
and of solar light, i. 56
effect of the opalescence of the atmosphere on the light of the
sun, i. 55
probable causes of the blueness of the sky, and the brightness of the
tints at sun-rise and sun-set, i. 58
solar spectrum, i. 58
myriads of ethereal waves constituting the seven colours of the, i.
58
fluorescent or degraded light, i. 60
experiment illustrating the change of heat into light, i. 62
absorption of invisible rays, by solids, liquids, and gases, i. 65
causes of earth light, i. 66
polarization of light and heat, i. 68, 69
by reflection and refraction, i. 69
relation of polarization to crystallization, i. 70, 71
M. Gassiot’s experiments on stratified electric light, i. 78
influence of magnetism on the stratified light, i. 78
cause of the stratified discharge, i. 85
effect of varied intensity on electric discharges, i. 86
action of magnetism and electricity on light, i. 90
delicate power of analysis in light, i. 95
Dr. Young’s establishment of the undulatory theory of light, i. 129
Drummond’s light, i. 132
coloured light obtained from the combustion of the salts of different
metals, i. 132
effects of light on vegetation, i. 168, 169
effects of light as an exciting cause in the vegetable world, i. 431

Lightning, spectrum of, i. 147

Ligneous tissue, i. 174, 175

Liliaceæ, structure and development of the, i. 388

Limboriei, structure and habitat of the, i. 310

Lime, carbonate of, different modifications assumed by, i. 74
chloride of, properties of, i. 19
oxalate of, formation of, i. 117

Limestones, probable history of the oldest, ii. 52
the nummulitic, ii. 53
the limestone formed by the Eozoön Canadense, ii. 54

Limnoria lignorum, structure of, ii. 203

Limpet, structure, food, and habitat of, ii. 238, 239

Limulus, fossil remains of, ii. 211

Lindsæeæ, characters of, i. 351

Lingbya, structure of, i. 213

Lingula flags, fossil animals composing the, ii. 53

Listera ovata, structure and mode of reproduction of, i. 399

Lithium, i. 3
spectrum analysis of, i. 133
existence of lithium in all three kingdoms of nature, i. 134
spectrum analysis of the rarefied vapour of, i. 142
effect of high temperature, i. 142, 143
chloride of, spectrum of, i. 146

Litmus, or orchil, from what obtained, i. 124, 303

Lituola, structure of the genus, ii. 37

Lituolidæ, characters of the family of, ii. 36, 37

Liver worts. _See_ Hepaticæ

Lobophylla angulosa, structure of, ii. 135, 136

Locomotion of some diatoms, i. 204

Lo-hao, a Chinese green dye, i. 124

Loligo vulgare, or squid, structure of, ii. 245, 246

Lomaria, characters of the genus, i. 357

Lomariopsis, characters of, i. 360

Loxades bursaria, structure of, ii. 72

Loxades bursaria, mode of propagation of, ii. 75

Lucifer, characters of the genus, ii. 200
matches, i. 17

Luminosity of the medusæ in warm seas, ii. 99
of Annelida, ii. 160
of Pyrosomidæ, ii. 226

Lycoperdon giganteum, structure, habitat, and fructification of, i. 267

Lycoperdon, structure and fructification of, i. 267

Lycopodiaceæ, or club mosses, characters of, i. 373
habitat and fructification of, i. 373, 374
uses to which they have been applied, i. 374

Lycopodium, or wolf’s-claw, characters of the genus, i. 374

Lycopodium clavatum, structure and habitat of, i. 374
inflammability of the dried spores of, i. 374

Lycopodium inundatum, structure and habitat of, i. 374

Lygodium articulatum, structure of, i. 363

Lymnæa, or pond snail, distoma of the, ii. 146

M

Macrocystis pyrifera, structure, habitat, and fructification of, i. 250

Macrura, characters of the, ii. 189
fossil remains of, ii. 211

Madder, dyes obtained from, i. 124, 125

Magenta, or aniline red, Dr. Hofmann’s discovery of, i. 122
how produced, i. 122
purple dye produced by mixing it with aniline, i. 123

Magnesium, i. 3, 4
spectrum of, i. 65
spectrum analysis of the rarefied vapour of, i. 142
shown to be one of the metals existing in the sun, i. 151-153
spectrum of the light of a magnesium flame, i. 153, 154
its use in photography, i. 154

Magnetism, i. 30
periodic and secular variations of, i. 30
probably stand in some periodic connection with the solar spots, i.
30, 31
probable cause of terrestrial magnetism, i. 31
difference between magnetic and electric currents, i. 33
relations between the force of magnetism and the atoms of matter, i.
75
all substances either magnetic or diamagnetic, i. 75
proof of the connection between the magnetic forces and crystalline
structure, i. 76
conduct of amorphous and isomorphous substances under magnetic
influence, i. 76
action of magnets upon matter most powerful in the line of maximum
density, i. 76
conditions of the position which crystals take with regard to the
magnetic force, i. 76
magnetic changes in the relations and distances between the ultimate
atoms of matter, i. 77
effect of magnetism on the stratified appearance of the electric
light, i. 78
causes of the polarity of a magnet, according to Ampère, i. 80
action of magnetism on the stratified discharges of electric light,
i. 82
illustration of the action of magnetism and electricity on light, i.
90

Maiden’s hair fern, structure and habitat of, i. 359

Malaxis paludosa, or bog malaxis, structure and mode of reproduction
of, i. 400

Malic acid, chemical combination forming, i. 97

Manchineel, poison of the, i. 426

Manganese, peroxide of, relative weight of the atoms of oxygen and
metal in, i. 99
atomic weight of, compared with that of hydrogen, i. 100
peroxide of, combination forming, i. 104

Manihot, or Cassava, food obtained from the, i. 426

Marasmius Oreades, spawn of, i. 262

Marattia salicina used as food, i. 365

Marattiaceæ, characters of the group, i. 364

Marchantia polymorpha, structure, development, fructification, and
habitat of, i. 317-320

Marchantiaceæ, characters of the order, i. 317

Mars, the planet, spectrum of, i. 158, 161

Marsh-gas, i. 118
amount of absorption of radiant heat by, i. 41

Marsilea, characters of the genus, i. 372

Marsileaceæ, or Rhizospermæ, characters of the tribe, i. 371

Matonineæ, characters of the group, i. 344

Matter, molecules of, i. 2
agency of electricity in the chemical composition and decomposition
of, i. 32
decomposing and elective power of, i. 35

Mauve, Dr. Hofmann’s discovery of the aniline colour, i. 122
at first made from orchil, i. 124
derived from guano, i. 125

Mediterranean sea, zones of algæ in the, i. 259
foraminifera, the ooze in the bed of the, ii. 51

Medusæ, form and structure of, ii. 91

Medusæ, pulmograde, form and structure of, ii. 91, 92
naked-eyed medusæ, ii. 91-96
mode of reproduction of, ii. 94
armed or stinging medusæ, ii. 99
luminosity of, in warm seas, ii. 99
development of medusa-buds, ii. 96
alternation of generation of hydræ and medusæ, ii. 96
covered-eyed medusæ, ii. 97
parasites of, ii. 99
abundance of species of, ii. 100
food of medusæ, ii. 101

Medusa-buds, development of, ii. 95

Medusiform zooids of hydrozoa, ii. 88, 89

Melanconiei, characters of the group of, i. 281, 282

Melanogaster, the red truffle of Bath, i. 268

Melanospermeæ, characters of, i. 181
marine forests of, i. 244
structure of the, i. 244, _et seq._

Mercury, conditions under which he may be habitable, i. 55

Mercury, its feeble affinity for iron, i. 98

Meridion circulare, structure and development of, i. 200, 201

Merulius lacrymans, the cause of dry rot in wood, i. 266

Mesocarpus, reproduction of, i. 217

Mesogloias, structure of, i. 245

Metals and their properties, i. 3
alkaline metals, i. 3
of alkaline earths, i. 3
from non-alkaline earths, i. 4
avidity of some of them for oxygen, i. 4
metals whose oxides are not reducible by heat, i. 4
diatomic metals, i. 4
triatomic metals, i. 5
conduction of heat and radiation, i. 5
vaporization, i. 5
spectra of volatilized metals, i. 64
coloured light obtained from the combustion of the salts of different
metals, i. 132
spectrum of, not always the same, i. 145
number of the metals of which the spectra has been determined i. 147
metals shown to exist in the sun, i. 151-153
and not to exist in it, i. 154
metals contained in every plant, i. 414

Meteorites probably not of solar origin, i. 153

Mica, opacity of, to the invisible rays, i. 65

Mignonette, weight of the perfume of, i. 45

Mildew of the vine, hop, &c., i. 295
the black mildews of the Azores and Ceylon, i. 297

Miliola, structure and habitat of, ii. 30
abundance of, in the seas of the Eocene period, ii. 31

Miliolidæ, characters of the order, ii. 30

Milk sap of plants, i. 425
vessels of plants, i. 417

Milleporæ complanata or palmipora, structure of, ii. 141

Mimosa pudica, irritability of the tissues of, i. 432

Mind and matter connection between, ii. 5

Molecules of matter, i. 2
cohesion of, i. 25
unit of mechanical force, i. 26
causes of the ethereal undulating motions of, i. 34, 35
_See_ Atoms

Mollusca, structure, habitat, and mode of reproduction of, ii. 229, _et
seq._
shells of the, ii. 232
naked, ii. 240
winged, ii. 240

Monas corpusculus, extreme minuteness of, ii. 63, 67
and of its ova, ii. 67

Monocotyledonous, or endogenous plants, structure, growth, and
reproduction of, i. 383
seeds of this class, i. 383
stems, or axes, i. 384
remarkable plants belonging to the monocotyledons, i. 387

Monostoma, or one-mouthed medusæ, structure and mode of reproduction
of, ii. 97

Monormia, habitat and structure of, i. 212

Moon, interception of the heat radiated by the full, by the earth’s
atmosphere, i. 55
its effect on the higher regions of the atmosphere, i. 55
chemical power of the moon’s light, i. 55

Moonstone, or adularia, fluorescent property of, i. 66

Moonwort, structure, and habitat of, i. 366

Morchella esculenta, the morel, i. 291
katsup made from, i. 292

Mordants for fixing dyes in cotton cloth, i. 125

Morphine, the probable narcotic principle of opium, i. 427

Mother-of-pearl, composition of, ii. 234

Motion, effect of, on molecular arrangement, i. 91

Moulds, fungus, on various substances, i. 285

Mucedines, structure of the, i. 283
the origin of all fermentation, i. 289

Mucorini, or moulds, structures of the, i. 296
habitat of the, i. 296, 297

Muriatic acid, formation of, i. 20
action of, upon ammonia, i. 120

Musci, or Mosses, structure and mode of reproduction of, i. 3
antheridia of, i. 324
sporangia of, i. 325
gemmæ or buds, i. 327
leaves of, i. 330
aquatic mosses, i. 331
peat, i. 333
uses of mosses, i. 334

Muscle, structure and functions of, ii. 2
functions of the muscles, ii. 5
electric currents formed in the muscles, ii. 7
muscular respiration, ii. 8

Mushrooms, i. 261
mycelium, or spawn, i. 262

Musk, power of absorption of radiant heat by the perfume of, i. 45

Mussel, structure of the gills of the common, ii. 230

Mycelium or mushroom spawn, i. 261, 262

Mysis, or opossum shrimps, structure of, ii. 199

Myxogastres, structure, habitat, and reproduction of, i. 269, 270
their Amœba-like motions, i. 270

N

Naïs, structure and habitat of the, ii. 152, 153

Naphtha, manufacture of, i. 120
uses to which it is applied, i. 120
sources of, in various parts of the world, i. 126
naphtha procured by the distillation of petroleum, i. 127

Naphthalin, production of, i. 127

Narcotics, exciting, known to almost all people, however savage, i. 427

Navicula, structure of, i. 198

Naviculæ, spontaneous locomotion of, i. 202

Nebulæ, spectra of various, i. 158-160, 163
constitution of the, i. 163
probable existence of primordial nebulous matter according to the
theories of Sir W. Herschel and La Place, i. 164

Nectria, characters of the genus, i. 295

Nectria Peziza, structure of, i. 295

Nematoid entozoa, structure and mode of reproduction of, ii. 146

Nemertes gigas, or great band worm, nervous system of, ii. 158

Neotteæ, characters of the British tribe of, i. 397, 398

Neottia Nidus-avis, structure and mode of reproduction of, i. 400

Nephrolepis tuberosa, characters and habitat of, i. 348

Nereis, structure of, ii. 157

Nereis diversicolor, mode of reproduction of, ii. 160

Nereocystis Lutkeana, structure and habitat of, i. 249

Nerve-force of animals, ii. 4, 6
chemical powers generated by, ii. 6

Nerves of animals, structure and functions of, ii. 5
electric currents in the, ii. 7
structure and functions of the brain and spinal cord, ii. 8
the nervous systems of the higher and lower animals, ii. 9-11

Nervous system of animals, ii. 5

Nickel, i. 4, 5
crystals of, formed artificially by electricity, i. 74
effect of heat on the magnetism of, i. 77
atomic weight of, compared with that of hydrogen, i. 100