INDEX 



553 



Nectaries, 208. 

 Nervature of leaves, 10. 

 Nessler's reagent, 68. 

 Nitrates, decomposition of, 75, 76. 



presence of, in plants, 68. 

 Nitric acid, 59, 71. 



detection of, 68. 

 Nitrification, 70. 

 Nitrogen determination, 60, 255. 



free as food, 59, 62. 



requirements of lower organ- 

 isms, 58. 

 Nitrometer, 245. 

 Nitromoiias, 68. 

 Nitrous oxide gas, effect of, on plants, 



281. 



Nuclein, 253. 

 Nucleus, 119. 

 Nutation, rotating, 488. 



spontaneous, 389. 



of roots, 485. 

 Nyctitropic movements, 481. 



movements, causes of, 484. 



Organic acids, behaviour of, in the 



Crassulaceae, 327. 

 acids, presence of, in plants, 324. 

 material, production of, 1. 

 Organised structures of plant cells, 



107. 



Orthotropic organs, 510. 

 Osmic acid, 121, 307. 

 Osmotic pressure, 154. 

 Oxalic acid solution, 267. 

 Oxygen, absorption of, in respira- 

 tion, 278. 

 compressed, 269. 

 consumption of, 260. 

 production of, in assimilation, 

 35. 



Palisade parenchyma, 11. 



Papilionaceae as collectors of Nitro- 

 gen, 62. 



Parasitic fungi, 100. 



Pasteur's food solution, 58. 



Pepsin, 252. 



Peptone, 252. 

 as food, 59. 



Perceptivity and power of reaction, 



475. 

 P. P. 



Periderm, 108. 



Pettenkofer's tubes, 266. 



Phenolphthalein, 267. 



Phosphorescence, 292. 



Phosphorus as food, 84. 



Photoepinastic nutations, 514. 



Phototactic swarmers, 424. 



Phycocyan, 20. 



Phycoerythrin, 20. 



Phycophsein, 20. 



Physiological elements, 254. 



Pigments, 339. 



Plagiotropic organs, 510. 



Planimeter, 522. 



Plasmodia, trophotropism of, 435. 



Plasmolysis, 150. 



Poisons, influence of, on plants, 137. 



Polarising apparatus, 115. 



Polarity, 505. 



Pollen grains, germination of, 346. 



Poroscope, 180. 



Potassium as food, 84. 



bichromate, 28. 

 Potential, electric, 157. 

 Precipitation membranes, 147, 149. 

 Pressure bottles, 151. 

 Proper angle of secondary roots, 



459. 



Proteid formation, seat of, 73. 

 Proteids, behaviour of, 251. 



formation of, 58. 



occurring in plants, 248. 



reactions of, 249. 

 Prothallium of ferns, 17. 

 Protoplasm, 116. 



diosmotic properties of, 145. 

 Protoplasmic communication, 117. 



movements, 417. 



influence of temperature upon, 

 419. 



causes of, 418. 



dependence of, on presence of 



Oxygen, 422. 

 Pyrenoid, 16. 



Eaphides, 74. 



.Rectangular division, principle of, 



373. 



Eectipetality, 495. 

 Reserve cellulose, 303. 

 Kesins, 338. 







