214 



INDEX 



Electrolytes in sap, 178, 186 

 Elfving, 29, 45, 95, 97 

 Energy absorbed by leaf, 201 



available for raising sap, 201 ff 



secretion, 201 



relations of leaves and roots, 204 



set free by respiration, 202 

 Errera, 29, 46 

 Ether, Influence of, on transpiration, 



9ff 

 Evaporation and tension in sap, 209 



and transpiration compared, 1 



engine, 206 



Function of, in transpiration, 4 ft' 

 in raising sap, 25, 203 

 Evaporation into various gases, 15 ft 



Raising sap, 25, 203 

 Ewart, 52, 69, 70, 79, 94, 100, 114, 116, 



118, 119, 122, 125, 127, 131, 138 

 Extraction, see sap-extraction 



Fading of leaves indicating a change 

 in water tracts, 54, 56, 57, 62 ff 



Freezing point and osmotic pressure, 

 relation of, 155, 190. 



Gas generated in lumina, 37 



pressure balanced against osmotic 

 pressure, 142 ff 



Pressure theory, 28 

 Gases, Transpiration into various, 9 ft' 

 Gelatine, Penetration of, into walls, 



29 ff 



Plugging of lumina by, 29 ff 

 Godlewski, 47, 79 

 Gravitational theory, 81 



Hales, 27, 46 



Hamburger, 174 



Hartig, 28, 46, 48, 49, 79, 93, 100 



Heat causing changes in conducting 



tracts, 54 ff, 62 ff 

 Heat causing changes in sap of stems, 

 53 ff, 62 ff 



used for extraction of sap of leaves, 

 177, 186 

 Henslow, 16, 26 



Ice in lumina, effect of, 38 ff 

 Illumination and osmotic pressure, 196 

 Imbibition, Function of, in transpira- 

 tion, 4 ff 

 Theory, 29 ff 84 



Jamin's Chain, 28 



Janse, 48, 51, 52, 54, 79, 102, 117, 118 



Johonnot, 106, 114 



Joly, 81, 87, 100, 119, 206 



Kammerling, 90, 100 

 Key, Reversing, for thermocouples, 

 160 



Laplace, 101, 115 

 Larmor, 2, 44, 46 



Leaf-cells, Osmotic pressure of, 139 

 Pressure and tension in, 140 

 Tensile strength of walls of, 

 198 ff 

 Liquid air for sap-extraction, 181 ff 

 Lumina blocked with gas, 37 

 gelatine, 29 ff 

 ice, 38 ff 

 paraffin, 32 ff 

 water vapour, 41 ff 

 of cells and Tracheae compared, 52 

 Transmission in, 29 ff, 53 



Marie and Gatin, 178, 189 

 Maximow, 189 

 Medullary rays, 47, 48, 51 

 Model of transpiring plant, 204 



Osmosis, Function of, in transpiration, 



4ff 

 Osmotic pressure and freezing point, 

 155, 190 



in plant organs, 192 

 of leaf cells, 4, 139 



a measure of tension in 



tracheae, 141, 193 

 and age, 197 

 height, 195 

 illumination, 196 

 resistance, 195 

 tenacity of cellulose, 198 

 Effect of carbon dioxide on, 



150 

 measured by external gas 



pressure, 142 ff 

 measured by freezing point, 

 190 ff 



plasmolysis, 142 

 Variations in, 194 

 Osmotic theory of Larmor, 44 

 Overton, 80 

 Oxydase in sap, 58 



Oxygen, Influence of, on transpiration, 

 9 ff 



Pappenheim, 98, 100 

 Paraffin casts of trachea?, 35 



for plugging trachea?, 32 ff 

 Pfeffer, 198 



Physical Theories, 27 ff, 81 ff 

 Pits, Bordered, Mechanism of, 98 

 Plasmolytic method for measuring 



osmotic pressure, 142 



