383 



NitroRen, loss from soils. 141, 142. 



nitrifying bacteria, 148, 149. 



plant nutrition, 133, 141, 3frl. 



sugar beets, 262. 

 Nobbe, germination, 44. 



Nordlinger, variations of temperature in forests, 7. 

 Normandy, thermal constants, 175, 176. 

 North Cape, Norway, germination, 39. 



gluten in wheat, 41. 

 Norway, acclimatization, 220. 



rye, 41. 

 Notation, phenological, 291, 293. 

 Nutrition, r61e of water, 114. 



of plants, 22, 140. 



Oak, phenology, 281-290. 



water consumption, 113. 

 Oats, cellulose, 18. 



drought, 337, 338. 



environment, 314. 



fertilizers, 162. 



light, 39. 



nitrogen, 136. 



phenological constant, 177. 



thermal constants, 320. 



TurkL«h, 217. 



water consumption, 113, 123. 

 Observations, phenological, 290-294. 

 Ohio, oats in, 338. 

 Optimum temperature, 36. 

 Orange. France, thermal constant of wheat, 39. 

 Oregon, soil temperatures, 62. 

 Orel, Russia, plant development, 231. 

 Orenburg, Russia, acclimatization, 231. 



season of vegetation, 221. 

 Orkneys, plant development, 39. 

 Orleansville, Algeria, thermal constants, 176. 

 Orotava, Teneriffe, acclimatization garden, 221. 

 O.xygen, absorption by plants, 18, 47-52. 



absorption by seeds, 46, 50. 



in asparagin, 49. 

 Ozone and thunderstorms, 341. 



Pagnoul, assimilation, 78, 79. 



fixation of nitrogen, 150, 161. 



sugar beets, 259-263. 

 Papilionaceae, fixation of nitrogen, 157. 

 Para, Brazil, insolation, 82. 



photochemical researches, 93, 94. 

 Paris, France, germination of wheat, 39. 



insolation, 82. 



.S'ec, also, Montsouris. 

 Parma, Itiily, phenology, 185. 



plant development, 231. 

 Pasteur, light and vegetation, 37. 



modification of bacteria, 157. 

 Pauchon, light and germination, 37, 42-52. 



northern vegetation, 40. 

 Peas, albuminoids, 18. 



fixation of nitrogen, 136, 153, 155, 160. 



thermal constant, 335-337. 



time of flowering, 242. 



water consumption, 113, 124. 

 Penhallow, soil temperatures, 53,63. 

 Pendleton, Oreg., soil temperatures, 62,63. 

 Pennsylvania, maize experiments, 333-334. 

 Pentads, in phenology, 273-274. 

 Pepper, acclimatization, 307. 



Percolation, 109. 



Periodic variation of climalo, 297. 



Periodical phenomena, 232. 



Perret, water and plant nutrition, 114. 



Petermann, fixation of nitrogen, 161. 



Pfeffer, asparagin, 49. 



thermal constants, 241. 

 Phantupimeter, 96, 273. 

 Phenological observations, 290-294. 

 Phenology, 167-294. 



climatic tables, 272-277. 

 epochs of, 167,181. 

 Linsser's law, 214,215. 

 lists of plants, 172, 191, 226, 242, 243. 

 temperature, 172,211. 

 thermal constants, 336. 

 summation of temperature, 279-290. 

 Philadelphia, Pa., bacteriological examination of 



air, 130. 

 Photantupimeter, 96, 273. 

 Photochemistry of sunshine, 92. 

 Photographic measurement of sunshine, 95. 

 Physiological constant, 224-230. 

 Physiological method, 6. 

 Piche evaporimeter, 106, 246, 273. 

 Pieper, germination, 44. 

 Pine, water consumption, 113. 



chlorophyl and light, 38. 

 Pinus. See Pine. 

 Plant growth, 15, 244, ;245. 



respiration, 18. 

 Plants, acclimatization, 215. 

 and air, 18. ' 

 climate, 22. 



fixation of nitrogen, 136-161. 

 phenological lists, 172, 191, 226, 239, 240. 

 soil moisture, 114. 

 sunshine, 168. 

 temperature, 53, 235, 236. 

 water drainage, 115. 

 water supply, 116-127. 

 Plat experiments, 352-355. 

 Plumb, maize, 332-333. 



plat experiments, 353. 

 Poa pratensis, 299, 307. 

 Poggioli, light and vegetation, 26. 

 Polar region, vegetation, 39. 

 Pollen, dissemination, 129, 291. 

 Polperro, England, epoch of awakening, IM, 185. 

 Postelberg, Au.stria, rainfall and harvest. 111. 

 Potato, cellulose, 18. 



date of planting, 309, 310. • 

 dryness and sunlight, 80. 

 harvest and water .supply, 127. 

 water consumption, 113-119. 

 Potsdam, Germany, atmospheric electricity, 131. 

 Pouillet, actinometer, 82. 

 Poulkova, Russia, phenology, 213-215. 

 PrazmofTski, fixation of nitrogen,[151-155. 

 Prediction of crop, 247-251, 363. 

 tables for, 272-277. 

 time of harvest, 175, 189. 

 Prillieux, nitrifying bacteria, 152. 

 Prize crops, 164. 



Progress of vegetation, 183, 185. 

 Protection from frost, 340. 

 Protein, 17. 

 Protoplasm, 16. 



