3S0 



INDEX 



Suction tension, and exudation pres- 

 sure of roots, 136-139 

 Sugar, protective influence in freez- 

 ing of, 126-127 

 Sulphur, bacteria, 256^257 

 cycle in nature, 69-70 

 in nutrition, 69-71 

 Suspensoids, 103 

 Swelling, 102-107 



Temperature, low, effects of, 124-129 

 Thermonasty, 337 

 Thermophilous organisms, 297-302 

 Thermotropism, 329-332 

 Thigmotropism, 334-335 

 Timiriazev, on field experiments, 84 



on light absorption, 33 



on transpiration, 155 

 Tissue composition, 7 

 Toxic properties of single salts, 74-76 

 Transpiration, 155-156 



balance, 159 



coefficient of, 161 



correlation with assimilation, 177- 

 178 



daily march of, 161-163 



efficiency of, 161, 177-178 



influence of, 184-187 



intensity of, 161 



leaf structure as factor in, 163-165 



methods of study, 156-161 



physical nature of, 161-163 



pull, 185-186, 188-189 



regulation of, 170-171 



relation to environment, 161-163 



stomatal and cuticular, 163-165 

 Transpiring organs, effects of en- 

 vironment on structure of, 

 178-180 

 Transpirographs, 160 

 Traube, on semipermeable mem- 

 branes, 110 

 Traumatropism, 332 

 Tree girdle, 347 

 Turgor pressure, 134-135 

 Twining movements, 333-335 



U 

 Urea in plants, 228 

 Ursprung, on cell turgor, 286 

 on rise of water, 189, 190 

 on suction tension, 135, 142, 183, 

 193 

 Uspensky, on hydrogen ions, 97 



V 

 Van't Hoff's law, 45-46, 276 

 Variegation, 24 

 Vegetative propagation, 356 

 Velamen of orchids, 151 

 Vernadsky, on rare elements in 



organisms, 67 

 Vessels, in plants, 191-192 



compression during water rise, 191- 



193 

 Vochting, on grafting, 364 

 Votchall, on water translocation, 



195 



W 



Wagner, on pot culture, 81 

 Walter, on drouth resistance, 179 

 Warburg, on respiration, 274-275 



on utilization of radiant energy, 32 

 Water, absorption, 130-154 



by aerial parts of plant, 150-154 

 amount absorbed, 130-132 

 gravitational, 144-145 



influence of environment on, 

 147-150 

 laws of entry into cell, 132-136 

 by roots, 147-150 

 from soil, 143-147 

 assimilation of, 13-17 

 available and unavailable, 143-147 

 balance in plants, 130-132 

 capillary, 144 



compression of vessels during as- 

 cent of, 191-193 

 conservation of, 173-174 

 content, in different parts of plants, 

 101-102 

 in seeds, 102 

 cultures, 8, 67-68 

 current, dynamics of, 184-187 



