846 INDEX. 



12— its absorbent property, 13 — its rind and epidermis in some 

 cases perform the office of leaves, 40. 



Bell glasses, their use in propagation by cuttings, 203 — of different 

 colours, 205. 



Bleeding, 244 — of Tines, preventive against 245. 



Blossom-buds, their identity with leaf-buds in the first stage of 

 organisation, 62. 



Bottom heat, 102 — its effects different from those resulting from 

 solar radiation, 93 — its natural amount, 103 — necessary for the 

 flowering of many tropical plants, 107 — degree of, communicated 

 to plants in pots, from the atmosphere .of a stove, 111 — its va- 

 riation agreeably to that of the soil of countries, 112. 



Branches, their vigour augmented by the abstraction of flowers and 

 fruit, 309 — effects of their being subjected to a widely different 

 temperature from that of the roots, ,50. 



Budding, propagation by, 210 — mode of operation, 212. 



Buds, the origin of branches, 15 — Hot the origin of roots, 15 — ad- 

 ventitious in roots, 22 — embryo, 30 — their relation to bulbs, 30 — 

 latent, 37 — mature, preferable to immature for the purpose of 

 propagation, 232 — the youngest most excitable, 232. 



Bulbs, 31, 114 — a species of bud, 37 — in arid regions, 320— effect of 

 scarring their centre, 210. 







Callus, 26 



Calyx, its situation and colour, 55 — its use, 67. 



Camellias, a method of propagating them, 239. 



Canker, 106. 



Cape heaths, drainage for, 275. 



Capillary tubes give hygrometrical force to tisBue, 17. 



Carbon, excess of, in seeds, 8 — its conversion into carbonic acid dur- 

 ing the process of germination, 9 — a component of the food of 

 plants, 18 — proportions of, in certain vegetable secretions, 76 

 — in seeds, 175, 179 — necessary to preserve their vitality, 179 — 

 requires its proportion altered before germination can be effect- 

 ed, 78. 



Carbonic acid, its formation during the process of germination, 9 — 

 its decomposition in plants by solar light; 41 — its mode of in- 

 troduction into the system of plants, 41 — its decomposition in 



