Goldschmidt, R., 220 ff. Goodale, H. D., 218 Gortner, R., 249 Graber, V., 256, 276 Grafting, heteroplastic, in animals, 46; in plants, 47 Gravitation, influence on organ formation in _Antennularia_, 194 ff.; on the egg of the frog, 141 Gray, J., 122 Gregory, 243 Groom, T. T., 280 Growth, termination of, 184; influence of cell size, 187 Gudernatsch, J. F., 155, 255, 342 Guyer, 124 Gynandromorphism, 209 Haeckel, 346 Half-embryos and whole embryos, 141, 142 Hammond, J. H., Jr., 269 Harden, 16 Hardesty, 358 Harmonious character of organism, 5, 6, 318 ff., 341 ff. Harrison, 31 Hartley, 111 Healing of wound, 187 Hektoen, 66 Heliotropism, 11 ff., 257 ff., 318; heredity of, 250 ff.; change of, 279, 280 ff.; and adaptation, 318 Helmholtz, 34 Hemoglobins, crystallographic measurements of, 64 ff. Henderson, L., 317 Henking, 198 ff. Herbst, C., 97, 147, 193, 306, 310 Heredity, of genus and species, 40 ff., 70, 151, 152; Mendelian, 70, 151 ff., 229 ff., 348; of sex, 198; sex-linked, 203 ff., 238 ff.; and evolution, 348 Herlant, M., 78 ff., 115 ff. Hermaphroditism, 89 ff., 212 ff., 216, 219 ff. _See also_ Inhibition _and_ Regeneration. Hertwig, O., 97, 123, 292 Hertwig, R., 95, 97 Hess, C., 278 Heterogeneous hybrids, purely maternal, 49, 50 Heterogeneous transplantation, Murphy’s experiments on, 44 ff.; limitation of, 46 Heteromorphosis, 155, 193-196 Hill, C., 25 _Hippiscus_, 199 Holmes, S. J., 269 Hoppe-Seyler, 351 Hormones, 145, 155, 181, 219; and Mendelian heredity, 245 ff., 348; and adaptation, 342. _See also_ Organ-forming substances. Huxley, 346 Hybridization, heterogeneous, in sea urchins, 48 ff., 73 ff.; in fishes, 51; in plants (Mendel’s), 230 ff. Hydrolytic enzymes, action of, 24; reversible action of, 24 ff. Hypertonic solution, 99, 111 ff. Imitation of cell structures by colloids, 39 Immortality, of cancer cells, 30; of somatic cells, 30 ff.; of life in general, 34 ff. Inheritance, of colour-blindness, 203, 204, 205; of eye pigment in _Drosophila_, 204 ff.; of pigments, 248 ff.; of acquired characters, 337 ff. Inhibition of regeneration in _Bryophyllum_, 162 ff. Inhibition of sexual characters of opposite sex, in pheasants, 218; lack of in hermaphrodites, 219; in _Bonellia_, 226 Instincts, 10 ff., 253 ff.; sexual, 198 ff. Intersexualism, 221 Intestine, formation of, 130 ff. Isoagglutinins, 66 ff., 92 Isolation of blastomeres, 136 ff. Jacoby, 352 Janda, V., 219 ff. Jansky, 67 Janssens, 242 Jennings, H. S., 264 ff. Jensen, 45 Joest, 46 Johannsen, W., 42, 333 Jones, 352 Jost, 90 Kammerer, P., 325, 337 ff. Kanitz, A., 290, 292, 296 Kastle, J. H., 26 ff. Kellogg, V. L., 279 Kelvin, 34 King, W. O. R., 50, 247 Klug, 351