INDEX. 



599 



Root, instances of their formation by 



the atom, 22 

 of their production by 



leaves, 23, 275 

 of theirremainingburied 



and torpid for many 



years, 262 



^ of vitality in, 30, 31 



lengthen at their points only, 17 



local motion of, in quest of fresh 



food, 19, 20 



matted, 439 



may be grafted, 350 



mode of increase after passing the 



embryo state, 17, 20 



most readily formed in darkness 



and moderate moisture, 25 



nature of their food, 28 



never inactive except when frozen, 



26 



perish if their formation be not 



speedily followed by the deve- 

 lopment of leaves, 25 



power of forming adventitious 



buds, 30 



— produced by removing a ring of 



bark, 25 



produced from various parts of a 



plant, 21 



propagating by cuttings of, 282 



proportion borne to the stem, 



variable, 26 

 — — the fact of their increasing in bulk 



without leaves or branches, ex- 

 plained, 78 

 the theory that they are only 



formed by the action of leaves, 



erroneous, 448 

 their action reciprocal with that 



of the leaves, 69 

 their deep penetration into cold 



soil a cause of canker, 148 



their feeding property depends on 



the hygrometrioal force of their 

 tissue, 18, 27 



their fitness for propagation de- 

 pends on their power of forming 

 adventitious buds, 30 



the remote cause of their forma- 

 tion, 25 



their great importance, and danger 



of destroying them, 19 



their hygrometrioal properties, 17 



■ their immediate cause involved in 



obscurity, 24 



their principal of&ce, 25 



their slender power of selecting 



food, 26 

 why their extreme points are 



called spongelets, 18 



Roses, mode of budding, 809 



-! neat mode of training, 426 



Royle, Dr., successful mode of packing 



seeds, 252 

 Runners, propagation by, 473 



Saddle grafting, 318 



SaJt as a manm-e, and mode of application, 



555 

 Saltpetre as a manure, 654 

 Salts, certain of them enter into the com- 

 position of the food of plants, 28 



nitrogenous, are connected with 



high vitality, 547 

 Sand employed in the propagation of 

 cuttings, 288, 293 



its composition, 527 



loose, unsuitable for plants, 530 



sometimes constitutes a most im- 



portant portion in the food of 



plants, 528 ' 

 Sap, accumulation of, 99 

 an inspissated state of, produced by 



a dry atmosphere, 612 



artificial obstacles to, 48 



ascending, its force, 67 



ascends partly in consequence of an 



attracting force by the leaves, 52 



ascent of, explained, 52 



cause of its flow, 49, 5.1 



course of, not prevented by wounds, 



45 



descending, 71 



when obstructed induces fruitful- 



uess, 352 



direction given to, by pruning, 362 



experiments in regard to the circu- 



latian of, 48, 51 

 falls back at night in consequence 



of cold, 53 

 flow of, materially influenced by the 



state of the weather, 50, 140 



generates buds, 32 



its ascending and descending cur- 

 rents communicate with difier- 



ent systems of veins in the 



leaves, 57 

 its changes during the course of its 



circulation, 40 

 its circulation affected by motion 



communicated to plants by wind, 



218 



its constituents, 45 



its transmission through the stem, 



40 

 may be compelled to organise itself 



externally as roots, 301 



motion of, different from its flow, 49 



superabundance of, detrimental to 



buds, 311 



