386 



Vincennes, Prance, acclimatization of barley, 41. 

 Vine and weather, 249-251, 295-298. 

 Vines, physiological studies, 15. 

 Violle, actinometer, 82, 97, 171, 273. 



conjugate bulbs, 97. 



sunlight, absorption by air, 85. 

 Vital principle, 15-16. 

 Vochting, light and vegetation, 79, 80. 

 Vogel, measurement of sunshine, 95. 



Walcott, rainfall and sugar crop of Barbados, 



344-350. 

 Warington, fertilizers, 103. 



nitrifying bacteria, 139. 



nitrogen in rain, 135. 

 Warren, thermophone, Go. 

 Washington, D. C, soil temperatures, 66. 

 Water, composition, 17. 



evaporation, 104. 



plant nutrition, 114. 



supply and plant growth, 116-127, 245. 

 Weather, artificial modification, 8. 



and prize crops, 165. 

 Weber, photographic measurement of sun- 

 whine, 95. 

 Welitschkowsky, percolation, 109. 

 Wheat, average yield, 144. 



cellulose and albuminoids, 18. 



climate and soil, 263-272, 314-318. 



date of flowering, 178. 



environment, 312-314. 



fertilizers, 162. 



growing period, 243. 



heat and light, 39, 41, 251-256. 



latitude, 73, 74. 



low temperatures, 339. 



nitrogen in rain, 142. 



phenology, 179, 278-290. 



sports, 303. 



sowing and harvest, 358-361. 



temperature and rain, 341-343. 



thermal constants, 1G9, 170, 177, 318-319. 



Wheat, water consumption, 113, 123. 



weather, 250. 

 Wheeler, fixation of nitrogen, 159. 

 Whipple, thermophone, 65. 

 Whitney, percolation, 109. 



soil thermometers, 65. 

 Wiesner, chlorophyl, 38. 



sun.shine and temperature, 71. 

 Wild, earth temperatures, 65. 

 Wilfarth, fixation of nitrogen, 136, 151-16.5. 

 Wind, data in phenology, 273. 



evaporation, 105, 107. 



plant growth, 19. 



vegetation, 129. 

 Wind-breaks, 340-341. 

 Wine crop and climate, 295-298. 



weather, 250, 256-259. 

 Winnipeg, Canada, sunshine, 100. 

 Winogradski, nitric ferment, 142. 

 Wisliczenus, atmospheric electricity, 131. 

 Wollkoff, actinometry, 82. 

 Wollny, crops and water, 116, 120, 124. 



pruning and tuber growth, 80. 



soil moisture, 110, 114, 115. 



soil temperatures, 57. 



transpiration, 113. 

 Woods, fixation of nitrogen, 160. 

 Woodward, transpiration, 69, 113. 

 Wright, wheat and temperature, 339, 340. 

 Wurttemberg, Germany, phenology, 235. 



Yakutsk, Siberia, acclimatization of grain, 220. 

 temperature range, 187. 



Zahner, soil temperatures, 62. 

 Zantedeschi, germination, 44. 

 Zea mays. {See also Corn and maize. ) 



germination, 28-36. 

 Ziegler, phenology, 236. 

 Zones of vegetation, 221. 



Linsser, 224. 

 Zurich, Switzerland, soil temperatures, 21. 



vegetation and light, 37. 



o 



