NDEX 



513 



tendons, differentiation, 432 

 tension, effects of, 432, 433 

 tetraploidy, 134 

 thyroid, brain-differentiation and, 396 



in late-fertilisation, 262 



and metamorphosis, 54, 427 



mosaic development, 199 



susceptibility of fields to, 190, 427 



tumours, fish, 392 

 thyroid activity, heredity, 436 

 thyroid hormone, 425 

 time of onset, gene-action, 408 

 time-relations, chemo-differentiation, 

 10, 215 



cleavage, 131 



gradient-fields, 307 



growth, 422 



hormones, 270 



nervous system, 383 



rate-genes, 409 

 tissue-culture {see also explantation), 



204 f., 209 f., 377, 433 

 toads, differential inhibition, 349 



sex-differentiation, 227, 258 

 Trip?ieustes, centrifugalisation, 221 

 Triton, Anuran sucker, heteroplastic 

 graft, 143 



balancer, 31, 176, 177 



balancer-field, 177, 236 



blastomeres isolated, 53, 90 



blastula, regulation, 94 



chimaeras,' 405, 407 



cleavage, nuclear equivalence, 85, 87 



compound embryos, 407 



cyclopia, 350, 352 



dependent differentiation, 44, 45, 46, 



47 

 double monsters, 75, 155, 156, 157, 

 158,329,351,352 



egg, constricted, 52, 85, 87, 89, 239, 



240, 350, 351, 352 

 eggs, fused, 90, 91 

 eyes, regulation, 242 

 gastrula, regulation, 89, 239, 240 

 gills, heteroplastic grafts, 45, 142, 



406 

 heterogenetic induction, 145 

 homoiogenetic induction, 145, 148, 



193 

 host-tissues, influence of, 147 

 labile determination, 49, 50, 94, 140, 



lens-differentiation, 55, 186, 188 

 lens-regeneration, 187, 237 



Triton, limb-regeneration, 271, 304, 



306, 307, 364 

 mosaic development, 195, 197 

 neural fold field, 239, 244 

 organiser, ii, 50, 51, 89, 135 f., 141, 



144, 146, 151, 310 

 regeneration-buds, 153, 271, 272, 



273, 364 



regional factors, 192, 193 



regional fields, 362, 363, 365 



regulation, 53, 90, 94, 216, 239, 240, 

 241, 242 



situs inversus, 75 



twinning, partial, 329, 351 



typical and atypical differentiation, 

 139, 314, 315, 316, 317 

 Trituriis, sex-differentiation, 258 



temperature-gradient, 138, 494 

 trochoblasts, Choetopteriis, 132 



Nereis, 132, 496 



Patella, 115 

 trophic effect, nerves, 174, 203, 363, 



387, 430_ 

 trophic inhibition, 292, 293, 295 

 trophoblast, 327 

 trout, double monsters, 75, 329, 331 



egg, over-ripeness, 261 



situs inversus, 75 



vertebrae, order of development, 



379 



trunk-organiser, 144, 146, 147, 490, 492 



trypaflavine, and sperm, 404 



Tubifex, blastomeres isolated, 113 

 double monsters, 113, 328 

 pole-plasms, 113, 171, 216 

 regulation, 113, 216 



Tiihularia, apical region, autonomy, 

 283 

 morphallaxis, 284, 287, 316 

 scale of reconstitution, 286, 287 



tumours, 54, 96, 213, 261, 392 

 organising effect, 153 



turbinate spiral, 370 



twinning, 245, 327 f. 



tympanic membrane, 178 



ultra-violet radiation, 88, loi, 108, 

 113, 263, 404 



tinification of organism, 424 



upper layer, bird, 159 f. 



urea, 183 



Urodela (see also Amblystoma, Amphi- 

 bia, Pleiirodeles, Triton, Triturus), 

 blastomeres isolated, 90 



