S60 INDEX. 



Seed-packing, 177. 



Seed-saving, 169. 



Seed-sowing, 159 — depth of seeds in the soil, 161. 



Sexes, the essential parts of a flower, 66. 



Shade necessary for cuttings, 205. 



Shifting plants in pots, 269. 



Shoots, young, their susceptibility of frost, 86 — " unripe," their di 

 minished capability of resisting frost, 84. 



Silex in solution absorbed by the Wheat plant, 17 — rejected by the 

 Pea, 17. 



Situation of a garden, 137. 



Soil, necessity of roots advancing into fresh, 20 — sterile, its effects in 

 accelerating fructification, 64 — its temperature and moisture 

 more important than its mineralogical quality, 108 — moisture 

 of the, 113 — its superior heat at top taken advantage of for the 

 cure of canker, 106 — effects of one too wet, 115 — effects of rapid 

 evaporation from, 120 — choice of, 137 — for seeds, 160 — itB ex- 

 haustion in pots, 269 — its deterioration by excretions of roots, 

 270 — necessity of its being changed, 271. 



Soils, appropriation of stocks to, 230— different, requisite for different 

 varieties, 832. 



Solar light, difference of its effects on plants when transmitted 

 through different coloured media, 205. 



Solar radiation cannot be imitated by bottom heat, so as to produce 

 a similar effect, 94. 



Solar rays, their exhausting effects on plants, under certain circum- 

 stances, 53 — the immediate cause of perspiration in plants, 

 126. 



Spongelets, their consistence, 11 — reason of the extreme points of 

 roots being so called, 11 — act as absorbents, 12 — are not special 

 organs, 13 — their force of absorption, 15. 



Spongioles abound in nitrogen, 13 — chiefly supply the waste occa- 

 sioned by perspiration, 18 — their importance, and the danger 

 of destroying them, 1 3 — are not protected by a fully organised 

 epidermis, 283. 



Succulent plants, their small proportion of roots, 15. 



Succulents, 321. 



Suckers, propagation by, 207 — their production, 209 — of the Fine- 

 apple, 209 



