v. Knaffl, E., 106 Knowlton, E. P., 292 Kofoid, C. A., 143 v. Körösy, 300 Korschelt, 361 Krakatau, 21 Kraus, 54 ff. Krogh, 292 Kryž, F., 335 Kupelwieser, H., 75 Lack of oxygen, influence on disintegration of tissue, 355 ff. Ladoff, S., 224 Lamarck, 6 _Laminaria_, 165 Landois, L., 53 Landsteiner, 66 _Lanice_, 143 ff. Lankester, E. R., 41 Leathes, J. B., 63 _Leucæna leucocephala_, 37 Levene, 351, 352 Lewis, 183, 344, 364 Light, influence on organ formation, in cave animals, 319 ff.; in _Proteus_, 325; in _Eudendrium_, 326. _See also_ Heliotropism. Lillie, F. R., 80, 82 ff., 87 ff., 93, 134, 191, 218, 292 Lillie, R. S., 101, 107, 110, 120 ff. Lipase, synthetic action of, 26 Living and dead matter, specific differences between, 14 ff. Lloyd, D. J., 111 Localization of Mendelian characters in individual chromosomes, 243, 244 Loeb, Leo, 30 ff., 45, 157, 170, 187 ff., 342 Loevenhart, A. S., 26 ff. _Lumbricus rubellus_, 46 _Lychnis dioica_, 217 _Lycopodium_, 93 _Lygæus_, 201 _Lymantria dispar_, 220 _Lymnæus_, 142 Lymphocytes, rôle of, 45 ff. Lyon, E. P., 134 ff. Macfadyen, A., 36 Maeterlinck, 255 Magnus, W., 60 Maltase, synthetic action of, 25 Marchal, P., 222 ff., 254 _Margelis_, 192 Mass of chromatin and of cytoplasm, 186 Mast, 269, 277 Mathews, A. P., 107, 363 Matthaei, G. L. C., 302 Maxwell, S. S., 270, 274, 277 McClendon, J. F., 122, 322 McClung, C. E., 68, 198 ff., 237 Megusar, 340 Meignon, 217 Meisenheimer, 225 Meltzer, S.J., 315 Membrane formation, 86 ff.; artificial, 98 ff. Mendel, G., 23, 229 ff. Mendelian characters, and evolution, 70, 348; and internal secretions, 243, 348; and enzymes, 247, 248, 249 Mendelian, factors of heredity, 4 ff., 68, 151 ff.; mutation, 66; dominant, 90; segregation, 229 ff. _See also_ Non-Mendelian inheritance. Mendelian heredity, mechanism of, 229 ff.; and chromosomes, 233 ff.; and hormones, 245 ff., 348; and enzymes, 247 ff. _Menidia_, 51, 321, 323 Merogony, 120, 126, 186 Merrifield, 303 Mesenchyme formation, 130 ff. Metamorphosis of tadpoles induced by thyroid, 155, 156 Metchnikoff, 361 ff., 367 ff. Michaelis, L., 62, 317 _Micrococcus prodigiosus_, 334 Micromeres, 132 ff. Minot, 362 Moenkhaus, W. J., 51, 344 Molisch, 20 Montgomery, 199, 234 Moore, A. R., 50, 247 ff., 280 Morgan, T. H., 46, 68, 89 ff., 95, 116, 126, 134, 141 ff., 173, 175, 184, 204 ff., 229 ff., 241 ff., 244, 347 Morse, M., 156, 353 Morton, J. J., 44 Moss, W. L., 67 Muller, H. J., 229, 231 ff. Murphy, J. B., 44 ff. Mutation, 6, 42, 243; and evolution, 347, 348 Myers, 55 Nathanson, 19 Natural death, 361 ff. Neilson, 110 Newman, 344 Newton’s Law, 253