Thought, 218-222, 227, 229, 230, 233; and imagery, concomitant but incommensurable, 219; digs below phenomenal surface, 219; distinguished from imagery, 218, 219; intellectual, steady, lucid and continuous, 229; not function of material organism, 233; power does not always degenerate with old age, 230; presupposes imagery, 221; proceeds with complete ease after initial exertion of imagination, 229; rational, 222, 224, 231, 233 —has spiritual soul for source and subject, 233 —reflective, 224 —spiritual, 222 —superorganic function of, 231; reflective, a superorganic function, 227; requires substrate of sensible images, 220 —on which it is objectively dependent, 222; some in all individuals, 219; spiritual, 222; untranslatable into adequate imagery, 219 Thrust faults, 107 Thrust planes like bedding planes, 108 Thymus, 299, 300, 301, 302; an ontogenetic rudiment, 301, 302 Thyroid glands, 292, 294, 295, 301 Thyroxin, 294 Time-value, 75, 82, 83, 84, 95, 96, 101; of geological formations, dubious, 75; of index fossils, 95, 96 —affords no basis for scientific certainty, 101 Tissue, lymphatic, 301 Tissue cells, 13, 14, 136, 156 Tonsils, 301 Tools, use of, by animals, 261 Trachelocerca, 138 Training, 244, 245, 256 Transformism, 3, 4, 6, 16, 24, 25, 32, 40, 43, 52, 53, 55, 56, 59, 61, 67, 69-72, 75, 80, 84, 109, 117, 123, 124, 126, 127, 131, 263, 268, 343; definition of, 3; impotent to explain origin of intelligence, 216, 233 _note_, 263; interpretation, not corollary, of fossil facts, 126; monophyletic, 69, 70; “natural” explanation of homology, 52; proofs for, empirical, aphoristic, and aposterioristic, 55, 56; rests on personal belief rather than on facts, 127; ultra-partisans of, 343; unconcerned with origin of life, 131; unifies origins in time, but not in space, 69 Transformist, 38 Transmutation, 6, 28, 35, 40, 50, 65, 69, 70, 71, 73, 123, 193 Trial and error, 241, 243 Triassic, 118, 119 Trilobites, 100, 117 Triploidy, 21, 22 Troglodyte, 34, 50, 314, type, 314 Troglodytes niger, 33, 314 Tropisms, 204 Tubercule of Darwin, not homologous with apex of horse’s ear, 303 Tubers, 160 Tubules, nephridial or excretory, 280