INDEX. 361 



Sulphuric acid, employed in drying air for the preservation of seed, 



m. 



Sulphurous acid gas, its escape from brick flues, 162 — its destructive 

 effects, 152. 



Suu'r rays, force of, 93. 



Superfluous matter thrown off by roots, 19. 



Stagnation of water about the roots of plants in pots, 275. 



Stamens, their parts and situation, 56 — their use, 68. 



Starch, its accumulation in seeds, 175. 



Stem bears a variable proportion to the roots, 15 — its origin, 21 — ■ 

 growth by the, 21 — is at first merely a small portion of cellular 

 tissue, 24 — its parts, 25, 28 — itB horizontal system, 24 — its per- 

 pendicular system, 24 — its property of forming leaf-buds, 80 — its 

 office, 32. 



Stems, processes by which wounds in them are healed, 25 — those 

 freely emitting roots may be more moulded up than others not 

 possessing such power, 278. 



Sterility, 65 — from cold and moisture, 84 — in seeds, causes of, 170 — 

 remedy for, 173. 



Stigma, 56. 



Stocks, appropriation of, to soils, 230 — their influence on grafts, 224 

 — necessity of a correspondence in growth between their hori- 

 zontal system and that of the graft or bud, 225 — their effects in 

 modifying the growth of the tree, 226 — their effects on fructifi- 

 cation, 227 — heading down, 234. 



Stomates, 88 — their number and size proportionate to the natural 

 nabits of plants, 39 — number of, in a square inch of the leaves 

 of various species, 39 — their position and adaptation, 51 — per- 

 mit the escape of vapour, 115. 



Stones, utility of, in soil, 119. 



Strontian, rejected by certain plants, 17. 



Structure of flowers, 55. 



Style, 66. 



Syringing, 61. 



System, horizontal, of stems, 24, 26— horizontal cellular, 24— perpen- 

 dicular, of stems, 24, 26. 



T. 

 Temperature, effects J great discrepancy in, as regards different por- 



