336 



INDEX OF SUBJECTS 



Preformation hypothesis, see Evolu- 

 tion. 



Prelocalization, 207, 222, 227, 241. 



Pressure, atmospheric, see Atmo- 

 spheric ; osmotic, see Osmotic ; ex- 

 periments on eggs of Frog, 34-37, 

 40-168 ; on eggs of Echinoderms, 

 37, 38, 185, 186 ; on eggs of Nereis, 

 39, 213 ; on eggs of Beroe, 39 ; as 

 a meansof preventing cell-division, 

 55, 56. 



Primary qualities, 300. 



Primitive streak absent, 104. 



Principle of germinal localization, 

 17. 



Principle of least surfaces, 41-44 ; 

 in spiral segmentation, 45-47 ; 

 disobeyed in radial and bilateral 

 types, 49. 



Proctodaeum, 9. 



Pronuclei, causes of union of, 130 ; 

 both male and female, not needed, 

 254. 



Proportionality, 293, 295; of parts 

 in partial larvae, 198-201, 290 ; in 

 one larva from two blastulae, 202. 



Prototroch, 213, 224. 



Protozoa, alteration of shape during 

 division, 48 ; senile decay, 65 ; 

 enucleate fragments of, 254 ; in 

 electric current, 93. 



Pseudo-gastrula, 237. 



Pseudo-triaster, -tetraster, 108, 129. 



Psychoid, 291, 297. 



Puberty, increase in growth-rate at, 

 65 ; increase in variability at, 73 ; 

 increase in value of correlation 

 coefficient at, 75, 76. 



Purposiveness, 286-289, 296, 299. 



Purposes, see Purposiveness. 



Pyrosoma, 24. 



Quadripolar mitosis, 263-265, 267. 

 Qualities, inheritable, see Inheritable. 

 Qualities, primary and secondary, 



300. 

 Qualitative division of nucleus, see 



Nucleus. 

 Quartettes of micromeres in ' spiral ' 



eggs, 25, 30, 213; isolated, 215, 221. 

 Quinine, effect on' fertilization, 128- 



130. 



Rabbit, decline of growth-rate, post- 

 natal, 62, 65 ; prenatal, 63. 



Radial segmentation, see Segmenta- 

 tion ; radial symmetry, see Sym- 

 metry. 



Rana esculenta, bilateral segmenta- 

 tion, 26, 28 ; obliquity of egg-axis, 



81, 163 ; cardinal temperature 

 points, 100; effects of salt, 118; 

 brain and eyes of tadpole removed, 

 175 ; fusca, segmentation, 28, 47, 

 53 ; cardinal temperature points, 

 97 ; influence of heat and cold, 

 97-100 ; effect of salts and other 

 substances, 119-123 ; artificial 

 parthenogenesis, 124 ; symmetry 

 of egg, 81, 163, 247, 248; formation 

 of lens, 275 ; palustris, symmetry 

 of egg, 81, 247 ; influence of cold, 

 100 ; temporaria, symmetry of 

 egg, 81, 163, 247, 248 ; virescens, 

 influence of cold, 100. 



Rate of cell-division, see Cell-division ; 

 of Development, see Development ; 

 of growth, see Growth. 



Ratio between nucleus and cyto- 

 plasm, 65, 268, 269. 



Rearrangement of cells, 11. 



Recapitulation theory, 12, 16. 



Red light, 94-96. 



Redistribution of yolk ' and proto- 

 plasm in inverted eggs, 84 ; of 

 organ-forming substances, 207, 

 208, 226, 227. 



Reducing agents, 131. 



Reflective judgement, 287, 288. 



Reflex movements of tadpoles de- 

 prived of brains, 176. 



Regeneration, 290 ; a form of de- 

 velopment, 1 ; of head of Tulularia, 

 114, 144 ; and Reserve Idioplasson, 

 159 ; of missing half-larva in Cteno- 

 phora, 210 ; in Ascidia, 239 ; 

 necessity of nucleus for, 254 ; of 

 lens, 276 ; nucleus in, 284, 285. 



Regulation, 290. 



Renilla, 55. 



Reproduction, sexual, 1 ; Aristotelian 

 view of, 13, 294-296. 



Reserve-idioplasm, 159, 161, 266. 



Resistance to injury, capacity for, 

 alters, 104. 



Respiration of Chick, 109, 113; of 

 Frog's egg, 110, 111, 112 ; of Teleo- 

 stean ova, 111 ; of Echinoid ova, 

 112. 



Responses to stimuli, 12, 20, 114, 

 272-277, 283-285. 



Restriction, genetic, 246, 277 ; see also 

 Potentialities, limitation of. 



Retardation of development, by sound 

 vibrations, 90 ; by light of certain 

 colours, 94-96 ; at low tempera- 

 tures, 97, 99, 100; without oxygen, 

 110, 111 ; by desiccation, 115; by 

 increased osmotic pressure, 117 ; 

 in absence of potassium, 146 ; and 



