Correlation of organs, 284

  Darwinism, 10

  Degeneration, 155, 279

  Digestion, 309;
    amoeba, 33;
    hydra, 37;
    worms, 47, 52;
    insects, 66;
    vertebrates, 73, 81

  Ear, 50, 64

  Echinoderms, 57

  Ectoderm, 37, 44

  Egg, 43

  Embryology, 43

  Emotions, 136, 230, 309

  Entoderm, 37, 44

  Environment, 158, 309;
    God immanent in, 161, 175;
    mirrored in human mind, 199

  Evolution, 3;
    conservative, 173

  Excretion,
    amoeba, 33;
    worms, 48, 53;
    vertebrates, 73, 81

  Faith, 209, 256

  Family, 180;
    origin of, Cf. 88, 178, 217;
    results of, 181

  Flagellata, 39

  Ganglion,
    supra-oesophageal, 49, 54;
    annelids, 64. 
    See Brain

  Gastraea, 45

  Gastrula, 44

  God, 244;
    knowable, 167

  Head,
    insect, 68;
    vertebrate, 75

  Heredity, mental and moral, 188

  Heroism, 193, 200, 227

  History, 15

  Hope, 262

  Huxley (quoted), 99, 171, 273

  Hydra, 37

  Insects, 65, 105

  Instinct, 127, 131

  Intellect, 117, 124

  Intelligence, 117

  Intelligent action, 128, 132

  Jaws,
    insects, 67;
    vertebrates, 73

  Knowledge, value of, 150, 229, 242

  Law, Divine, 245

  Locomotion and nervous development, 61. 
    See also Muscular System

  Love, 139, 180, 243

  Magosphaera, 40

  Mammals, 85, 92;
    oviparous, 86;
    marsupial, 87;
    placental, 88;
    temporarily surpassed by reptiles, 195

  Man, 210, 219;
    anatomical characteristics, 92;
    mental and moral characteristics, 99, 112, 147, 150, 219, 242;
    relation to nature, 210;
    animal, 213;
    moral, 220;
    religious, 224;
    hero, 227;
    future, 228, 231

  Materialism, 165

  Mesoderm, 45

  Mind, 115, 144;
    amoeba, 33

  Mollusks, 58, 106

  Motives, 136, 148;
    sequence of, 143

  Muscular system, 309;
    hydra, 38;
    worms, 62;
    insects, 68;
    vertebrates, 73, 108, 216

  Naegeli, 288

  Natural selection, 12, 152, 278

  Nature, 9, 28

  Neo-Darwinians and Neo-Lamarckians, 296

  Nervous system, 102;
    hydra, 38;
    turbellaria, 48;
    mollusks, 59;
    annelids, 63;
    insects, 69;
    vertebrates, 74

  Notochord, 74, 79

  Ontogenesis, 26

  Phylogenesis, 26, 100, 310

  Placenta, 88