INDEX. 



Absorptiok, force of, in spongelets, 19 



most energetically carried 



on by the spongioles, 456 

 power of, poBsesaed by cer- 

 tain soils, 548 



rate of, in certain plants, 59 



Acetate of lime, solution of, rejected by 



roots, 27 

 Acorns, best mode of packing, 251 

 jEgUopian wheat, origin of, 483 

 Aerial roots are sources of nourishment 

 which dry up when most 

 wanted, 142 

 — explanation of the phenome- 

 non of, 141 

 Affinity, elective, 499 

 Air and moisture, axioms relating to, 



212 

 currents of, . greatly increase the 



effects of heat and light, 101 

 drying of, by means of sulphuric 



acid, 244 * 

 evil arising from the external, being 



colder than that under bell- 

 glasses, 293 



importance of free, to fruit, 101 



importance of preserving, in an 



uniform state, 293 

 in cold pits, necessity of being kept 



in motion, 217 

 7 — in hothouses, 215 

 ■ introduction of heated, to plant 



compartments, 223 

 moisture of, at London and other 



parts of the world, 185 

 purification o^ by plants during the 



day, 62, 514 



roots growing in, 21 



Air-passages penetrate plants in all dii-ec- 



tions, 134 

 Alburnum, 40 



its connexion with the spon- 



gelet, 18 

 ■ its importance, 46 



Alburnum, its quantity proportionate to 

 the number of buds, 265 



offices perfornied by, 45 



— instance of being cut into 



and preserved for centu- 

 ries, 39 

 Alburnous substance, 265 

 Alkaline substances, their effects upon 



germinating seeds, 235 

 Alpine plants, probable cause of the diffi- 

 culty iu growing, 218 

 American aloe, the number of years 



before it flowers, 93 

 American plants, points to be attended to 

 in their culture, 532 

 soil for, 531 



Ammonia employed to promote germina- 

 tion, 236 



its extreme solubility in water, 



549 . 



proportion of, in rain water, 28 



power of soils generally to ab- 



sorb, 547 

 Ammoniaoai manure, effects of,. 550 

 Amputating, effects of, 405 

 Anatomy of leaves, 66 

 Anemone japonica, adventitious buds in' 



roots of, 31 

 Ansesthetic substances, effect of, 8 

 Annuals, oleraceous, 166 

 Annual rest of plants, 506 

 Anther, 81 

 Antherids, 10 

 Antherozoids, and spores, phenomena 



attending their fertilisation, 11 

 Apple-tree, pruning of, 374 

 Apricot-tre^ pruning of, 387 

 Aquatic plants, conditions under which 



they exist, 160 

 — mode of treating to in- 

 duce themto flower.lSO 

 require the water to be 



brought to a fitting 



heat, ISO 



