258 



GROWTH HORMONES IN PLANTS 



Curvature, geotropic, 169, 175-178 



nastic, 123, 120 



phototropic, 131, 143-146 



traumatic, 214 

 Czaja, A. T., 60, 79, 101, 118, 119, 



121 

 Czapek, F., 200 



D 



Dagys, J., 103 



Darwin, C, 3, 164, 199, 213, 4 

 Darwin, F., 133, 172 

 Das, G. P., 217 

 Daucus, 164 



Decapitation, method of, 20-23, 21 

 Destruction of growth substance, 

 by enzymes, 98 

 by Ught, 93 

 Detection of growth substances, in 

 fluids, 24, 29 

 {See also Extraction; Test 

 methods) 

 Dewers. F., 200 

 Dextrose agar, for extracting growth 



substance, 25, 207 

 Diastase, occurrence of growth sub- 

 stance in, 12, 118 

 Diet, effect of, on growth-substance 



production, 67-69, 68 

 Diffusion of growth substances, into 

 agar, 25 

 from agar into plant, 25, 79 

 and transport in plant, 76 

 Diffusion coefficient of growth sub- 

 stance, 58, 59, 167, 207 

 Dijkman, M. J., 60, 97, 192 

 Dillewijn, C. van, 87, 88, 93, 132, 



147 

 Distribution of growth substance, in 

 coleoptiles (Avena), 57 

 in hypocotyls, 60 

 in leaves, 93-95, 94 

 in roots, 101 

 Dixon, H. H., 217 

 Dolk, H. E., 27. 31, 32, 58. 64, 89, 

 91, 115, 135, 144, 157. 173, 178- 

 179, 180-181, 183, 186-187 



Drechsel, O., 12, 22, 56, 151, 152 



rf-value, 28, 29, 28 



Dyes, effect of, 66, 101, 160, 161, 215 



E 



Elaeagnus, 59 



Electric potential, comparison of 

 photo- and geotropic. 196 

 during geotropic curvature, 182- 



185, 196, 209-210 

 during phototropic curvature, 



15^160 

 and transport of growth sub- 

 stance, 78-79, 159-160, 183, 

 185, 194 

 Electrophoresis, 78-79 



{See also Electric potential and 

 transport) 

 Electrotropism, 182-185, 184, 185, 



194, 209 

 Elfving. F.. 197, 203 

 Endosperm, as supply of growth 



substance, 58, 62, 65, 90 

 Enzymes, definition of, 2 



and destruction of growth sub- 

 stance, 98 

 Eosin, effect of, on phototropic 

 response, 161 

 on roots, 101, 160 

 Epinasty, 123, 120 

 Erman, C, 87 

 Erxleben, H., 15, 33, 43-51, 59, 



62, 63, 65, 67, 69, 100, 102 

 Erythrosin, effect of, on phototropic 

 response, 160 

 on roots. 66, 101 

 Ether purification, method of, 41 

 Ethylene, effect of, on formation 

 of growth substance, 74 

 on geotropism, 192 

 on growth, 75 

 on roots, 66 

 Euglena, 103 



Extraction of growth substance, 

 with alcohol, 26 

 with chloroform. 26 

 by diffusion, 25 

 with ether, 41-42 



