Types, 54, 55, 66, 83, 84, 92, 116-120, 123, 124, 141, 328, 329, 334, 335, 336; Ancestral, 92, 117, 276; annectant, 92; approximation in, 66; common ancestral, 83; Crô-Magnon, 332, 334, 335; no evidence of its descent from Neanderthal type, 334; generalized, 54, 55, 81, 84; are abstractions, 54, 55; generic, 116, 117; persistence of, 118, 123; Grimaldi, 332; intergradent, 83; invertebrate, 117; modern, 116, 120, 334; Neanderthaloid, 329, 335; persistent, 116; persistence of, 119; phyletic, 116, 117; permanence of, 118; specific, 116, 141 —persistence of, 118, 123; fossil doctrine of their invariable sequence, 104, 312 Ultramicron, 144, 168; destitute of reproductive power, 168; may not be natural unit, 168; of colloidal solutions, 168 Ultramicroscope, 140, 144; limit of, 140 Ultraspiritualism of Descartes, 199, 202 Ultra-violet rays, 148, 184 Unchange, not explained by theory of exchange, 123 Understanding, 235 Ungulates, 78, 82; fossil, 82 Uniformitarianism, 67, 68 Uniformity of nature, 149, 186; only justification for reconstruction of the past, 149; principle of, 169 Union of soul and body, according to Descartes, 198, 199 Units, 144, 162, 163, 166, 167, 168, 170, 174-177, 199-201; difference between, 170; inorganic, 144, 163, 166, 170, 174, 175, 176, 177, 201 —and living, 170, 175-177 —incapable of other than transitive action, 174, 177; living and non-living, 199, 200; natural, 168; new, of life to be discovered, 167; of nature, non-living, 162, 163 Universe, Stone Book of, 127 Uranium, 146 Urea, 173 Ureter, 282 Uroleptus mobilis, 138, 161 Urosthenic, 270 Ursus spelaeus, 326, 329 Use, 291 Utility, 291 Valence, 165; atomic, 165; molecular (residual), 165 Variation, 9, 18, 40, 41, 42, 45, 63, 64, 88, 303; agencies of, 42; cause of modification, 41; converges and diverges, 63, 64; fluctuational, 9, 303; heritable, 42; intra-specific, 43; mutational, a change of loss, 18; non-inheritable, 42; process of diversifying, 40, 45; trans-specific, 43, 88 —no experimental evidence of, 45 Varieties, 334, 342 Vault, 329, 332 Vegetarians, 236 Versatility, 257, 258, 259; distinctive mark of intelligence, 257, 258 Vertebræ, 279 Vertebrate, 60 Vertebrata, 119, 270, 271, 279-284, 292, 297, 300, 302; amniotic, 280-282; anamniotic, 280, 282 Vestigial remnants, 299 Viability, 4, 5, 25, 26, 43, 44 Vibration, 209; pure, 209; without vibrant medium, 209 Vinegar fly, 19, 85 Violet, 25, 159 Visceral arches and clefts, 278, 279 Visualist, 219