INDEX 



509 



neural tube, differentiation, 374 



explanted, 203, 392 



inductive capacity of, 147, 148, 193 

 neurenteric canal, 27 

 neurobiotaxis, 389 

 neuroblasts, 33, 377, 380 

 neuron, differentiation, 377, 380, 384, 

 386 



proliferation, 383 f. 

 neurula, 13, 27 

 newt, see Triton 

 non-specific attraction, 392 

 nose-field, 237 

 nostril, 31, 180 

 notochord, 18, 21, 28, 50, 161 



differentiation, 183, 220, 314, 316, 



317,484 



explanted, 202, 203 



inductive capacity of, 145, 374 



presumptive, 22, 23, 24 

 nuclear division, 43, 84, 85, 87, 397 

 nucleic acid, 132 

 nucleus, 46, 119, 404 f. 



Obelia, polarity, 63, 64 

 Oligochaetes, cleavage, 113 



double monsters, 113, 330 



gradients, 274, 275, 277 



organiser, 166 

 ontogeny, 8 

 operculum, Anura, 180, 233, 428 



Anura, polarity, 360 



asymmetry, Polychaetes, 71 

 ophiopluteus, 81 

 optic cup, 30, 374 



determination, 244 



lens-inducingcapacity,5l,54, 183 f., 

 184, 185, 188, 237 

 optic lobes, determination, 245, 246 

 optic stalk, determination, 244, 249 

 organ-fields, 193, 221, 228 

 organ-forming substances, 108, 114, 



117 f., 2i6, 311 

 " organic points ", Bonnet's theory of, 6 

 Organisationsfeld, 274 

 organiser, amphibian, ii, 12, 49, 50 f., 

 51, 52, 80 f., 89, 134 f., 149, 158, 

 310, 317 f., 327, 488 



amphibian, extract, 154 



amphibian, heteroplastic grafts, 141 



amphibian, " infection" by, 151, 152 



amphibian, regional potencies, 144, 

 146, 490 



bird, 159 f., 160, 162 



organiser, bird, determination, 163 



bird, killed, 163 



Corymorplui, 164, 290, 291 



Hydra, 164, 165 



Planaria, 166, 167 



Sabella, 165, 289 



sea-urchin, 166, 169, 321, 322, 325 

 organising substance, 154, 497 

 organism, unification, 424 

 orientation, of organiser, 149 



of primitive streak, 161 

 ovarian hormones, 177 

 ovaries, bird, asymmetry, 264, 266 



bird, mosaic development, 205 



and egg-polarity, 35, 63 

 over-ripeness, of egg, 95, 96, 261 

 oxygen, 60, 280, 288 

 owl, skull, asymmetry, 70 



Palaemon, chela-growth, 370, 371 



eye-regeneration, 360, 361 

 palato-quadrate, 178 

 pancreas, explanted, 203 

 pangenesis, Darwin's theory of, 4 

 Papilio, mosaic development, 206 

 parabiotic twins, 256, 257, 383, 385 

 Paracentrotus, 313 



organiser, 166 f., 169, 322 



regional potencies, 10 1 f., 102, 104 

 pars nervosa, 179 

 parthenogenesis, artificial, 37, 133 

 partition-coefficient (growth), 366 

 Patella, isolated blastomeres, 115 

 Patiria, cleavage, 83 f. 



double monsters, 328 



polarity, 313 



regulation, loi 

 Pecteii, metaplasia, 212, 213 

 Pelmatohydra, heteroplastic grafts, 164 

 Pelobates, eye-regulation, 244 

 Pennaria, reconstitution, 66 

 pericardial cavity, 32 

 peristomial mesoderm, 20 

 permeability, 108 

 Perophora, differential inhibition, 293, 



425 

 Petromyzon, neural tube, 182 

 Phagocata, regenerative capacity, 298 

 Phalhisia, partial larvae, 123 

 pharynx, Planarian, 165, 167 

 Pheretima, gradients, 274 

 Phialidiuni, polarity, 62 

 phosphatase activity, 205 

 phylogeny, 8 



