INDEX 



Nettles, inheritance in, 228. 

 Nitrogen-fixing bacteria, 76. 

 Nitrogen loss through plant growth, 



71. 



Noctiluca, 79, 80. 

 Normal curve, 202. 

 Notochord, 112. 

 Nucleo-plasma relation, 99. 

 Nucleus, 20. 

 Nutrient solutions, 70. 



CEnothera, mutations, 208. 



Ontogenesis, 129. 



Organic response, 242. 



Organic synthesis, 52. 



Organisms, destruction of, 72 ; 



putrefactive, 73. 

 Organs, sensory, 107. 

 Origin of species, 306. 

 Oxidation, 48 ; chemistry of, 65. 

 Oxygen, role of, in metabolism, 62. 

 Ozone, 49. 



Palcemon, heteromorphosis, 190. 



Papilio turnus, 302. 



Paramecium, 34; electric response, 



251 ; conjugation in, 165 ; pure 



lines in, 223. . 

 Parasitic and saprophytic nutrition, 



58. 

 Parasitism, in Protozoa, 283 ; 



in worms, 285 ; in. insects, 287 ; 



in plants, 292. 

 Parthenogenesis, 167 ; in wasps, 



168; artificial, 169, 170; in 



in plants, 183. 



Peas, Mendel's experiments, 225. 

 Pelagic adaptation, 261. 

 Pelagonemertes, 261. 

 Pepsin, 83. 

 Phagocytes, 29. 



Phosphorescent animals, 79-82. 

 Photophores, 264. 

 Photosynthesis, 53. 

 Phylloxera, 295. 

 Pipa, 272. 

 Plants, association among, 290 ; 



parasitism in, 292; response in, 



250 ; sexual reproduction, 174 ; 



evolution of, 184 ; fission in, 135. 



Plastogamy, 151. 

 Poisons, 66. 

 Pollen-tube, 179. 

 Polyembryony, 189. 

 Polymorphism in species, 301 ; in 



ants, 303. 

 Preformation, 191. 

 Proteins, 10 ; production of, in 



the organism, 55. 

 Protista, 26. 

 Protoplasm, chemistry, 8 ; physics, 



of, 14 ; organization of, 17. 

 Protozoa, 26 ; parasitism in, 284 ; 



movements of, 77 ; conjugation 



in, 164. 



Pseudopodia, 28. 

 Pure lines, 221. 

 Putrefactive organisms, 74. 



Reaction, 243. 



Reduction, 153. 



Regression, filial, 219. 



Regulation, 185 ; in Hydra, 186 ; 



Stentor, 187 ; sea-urchin blas- 



tulse, 188. 

 Reproduction as a growth process, 



131 ; in plants, 174 ; sexual, 141. 

 Respiration, 64. 

 Response, organic, 242 ; nature of, 



246 ; electric, 243 ; unsymmetri- 



cal, 248; adaptive, 253; mor- 



phogenetic, 256. 

 Reversion, 232. 



Rhinoceros beetles, variation, 205 

 Rust intwheat, 292. 



Sacculina, 289. 



Salts, inorganic, importance of, 

 10. 



Sea-urchin larvae, regeneration, 

 188. 



Secretin, 89. 



Secretion, 41 ; internal and ex- 

 ternal, 86. 



Seeds, stored foods in, 128 ; dis- 

 persal, 278. 



Seed plants, reproduction in, 177, 

 180. 



Segmentation, metameric, 135. 



Selection, Natural, 316. 



