404 
Recent Agricultural PuhlicationB. 
analysis of the seed, and its percentages of ash, fat, sugar, gum, 
starch, cellulose, albuminoids, and amides. Changes during germi- 
nation. Germination of tubers (potato, Jerusalem artichoke) and 
bulbs. Formation of buds of perennial plants. 
2. Assimilation of Carbon. — Characters of chlorophyll, the green 
colouring matter of plants. Decomposition of carbonic acid by 
green plants ; influence of the condition of the leaf ; different action 
of the two sides of the leaf ; influence of the composition of the 
atmosphere. The decomposition of carbonic acid by the leaves is 
the origin of the organic matter in the soil. 
3. Assimilation of Nitrogen, whether in the form of nitrates, of 
ammonia, or of organic matter. Role of atmospheric nitrogen. 
Fixation of ammonia and of nitrogen in the soil. Fixation of 
atmospheric nitrogen by leguminous plants (experiments of Hell- 
riegel and AVilfarth, and of Breal). 
4. Mineral Composition of Plants. — Quantities of ash left by 
leaves, wood, roots, stems. Chemical ingredients of plant ashes ; 
modes of estimation. 
5. Mineral Nutrition of Plants. — Influence of various mineral 
ingredients — phosphoric acid, potash, lime, magnesia, chlorides, 
silica. 
6. Assimilation of Mineral Matters.- — Conditions in which 
mineral substances exist in plants. The process of diffusion. 
Accumulation, in the leaves, of substances soluble in water charged 
with carbonic acid, but insoluble in pure water. 
7. Respiration. — Conditions which regulate its activity. Oxygen 
essential to the life of plants. Influence of the compo.sition of the 
atmosphere upon the production of carbonic acid. Heat arising 
from plant-respiration. Matters consumed in respiration. Com- 
parison of respiration with assimilation. 
8. Constituents of Plants. — Carbo-hydrates : sugars, gums, 
dextrins, starches, celluloses. Ternary compounds, other than 
carbo-hydrates : fats, tannins, vegetable acids (oxalic, lactic, malic, 
tartaric, citric), volatile acids (formic, acetic, butyric), resins 
(caoutchouc, gutta-percha, turpentine), essences (of rose, jasmin, 
orange, <tc.). Nitrogenous compounds : alkaloids (nicotine, mor- 
phine, quinine, strychnine, Ac.), amides (asparagine, leucine, tyrosine, 
glutamine), albuminoids (vegetable albumin, vegetable casein, 
gluten). 
9. Movement of Water in Plants. — Absorption of water by roots. 
Ascent of water in the vessels of plants. Transpiration (or evapo- 
ration from leaves) : its extent in different plants, its amount com- 
pared with absorption ; influence of the age of the leaves, of direct 
or indirect sunlight, and of different hours of day and night. Effect 
of transpiration in the distribution of species. 
10. Growth and Maturation. — Predominance, in the development 
of herbixceous plants, firstly, of the root, and secondly, of the leaf, 
followed by flowering and ripening. Changes during ripening. 
Migi’ation within the plant of nutrient substances. Accumulation 
of reserve materials. Ripening of woody plants. 
