INDEX. 353 



Light, detrimental to the germination of seeds, 9 — ^its absence con- 

 ducive to the formation of carbonic acid, 9 — conducive to the 

 formation of roots, 14. 



Light, by its action on the leaves a principal agent in forming secre- 

 tions, 62 — ^its efifect on the colour of leaves, 62 — ^its agency in 

 changing the secretion of fruits, 74 — ^its stimulating effects, 118 

 — ^its effect in altering and decomposing the fluids of plants, 116 

 — an abundance o^ with low temperature, tends to inspissate 

 the sap, 325 — solar, its influence on vegetable life, 41 — effects a 

 decomposition of carbonic acid in plants, 41— occasions the ex- 

 trication of nitrogen in plants, 41 — ^promotes insensible perspi- 

 ration in plants, 41, 48 — its full intensity can be safely borne by 

 some species but not by others, 53 — more necessary than changa 

 of air in imparting flavour to fruits, 162. 



Lights of fruiting-houses, their removal, 166. 



Lignification depends on the action of leaves, 23 — sedimentary mat- 

 ter of; 266. 



Xdme, applied for the germination of seeds, 166 — ent«rg into the 

 organisation of plants, 336. 



Liquid manure, 340. 



M. 

 Male flowers in unisexual plants, 82. 

 Manures, 388 — their application, 340 — ^principles of their eonstitn- 



tion, 889 — their action, 340 — time of their application, 341 — 



manner of their application, 842 — ^Uquid, 340. 

 Marsh plants, 114. 

 Maturation of fruit, 69. 

 Medullary rays, 27. 

 Melons, preservation of the purity of their races, 303 — effects of their 



roots being immersed in water, 116. 

 Metallic substances in plants, 336, 336. 



Metamorphoses of the parts of plants, 67 — example ot 67, 61, 178. 

 Mildew, 61, 123 — in wheat, attributed to a superabundant absorption 



of moisture, 61. 

 Mineral substances in plants, 336. 

 Moisture, atmospheric, when amounting to saturation, occasions a 



cessation of perspiration in plants, 48 — ^its absorption by leavei^ 



ei_connect«d with temperaturey 125 — ^its range, 127 — ^ita meaa 



