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its way as it were for moisture by a rotary motion which lie termed 

 circumnutation, and how the hairs of the root adhere to the particles of 

 soil and draw their nourishment from it. 



It was also shown how at the same time the plumule pushes its 

 way to the surface, exhibiting by its single leaf its characteristic class as 

 a Monocotyledonous plant. The lecturer then explained the chemical 

 action of the leaf whereby the green chlorophyl of the leaves decom- 

 poses the carbonic acid, fixing the carbon, and giving off the oxygen, 

 this carbon being a particular plant product with which the greater part 

 of its structure is built. 



It was shown that the nutriment the plant derives from the ground 

 can only be taken up by the plant in a soluble form, hence the value of 

 a proper exposure of the soil to the action of the atmosphere was a 

 necessary work for the agriculturalist, as well as the necessity for a 

 proper supply of moisture. The part played by the rootlets in absorbing 

 the proper nutriment was shown from the recent observations of 

 botanists, to be due to the power they possess of decomposing the salts of 

 the earth, by which the latter become available for the plant's use. It was 

 shown by analysis, what salts the wheat plant derives, from the soil, 

 but in what way its power of selection is made is a point Physiologists 

 have not yet determined. 



By the aid of a series of diagrams it was explained that the plant is 

 built up of a series of cells having powers of reproduction, and that 

 each parent cell gives rise to other cells of the same kind, each 

 with its own proper function. Each cell of the plant has a vital 

 chemical and physical action, and the lecturer observed that the action 

 of these may be compared to the division of labor in a hive of bees, 

 one set building up one part, and the other set building up other parts 

 of the structure, one set feeding another set with their proper 

 nourishment, and storing up starch for future use, as the bees do 

 their honey. The connection between the roots buried in the soil and 

 the leaves exposed to the air was explained by the action of osmosis and 

 transpiration. By osmosis — in the absorption of the more fluid contents 

 of the lower cells, through the cell walls, into the upper cells which are 

 rendered more dense, and by the transpiration of water by the leaves, the 

 whole being a diffusion of fluids controlled in some way by its taking 

 place in a living apparatus. It was further explained that different 

 parts of the plant have different chemical constituents, for example an 

 analysis of the wheat and the wheat straw would show they were not 

 of like constituents, for 100 lbs. weight of the wheat possessed about 

 30 lbs. of potash and soda, while 100 lbs. of straw possessed only 11 lbs. ; 

 and the wheat would have only 1 lb. of silica, while the straw had 66 lbs. 

 It was stated that the contents of the plant cells called protoplasm is the 

 seat of active chemical process and vital activity, which collectively are 

 now termed metabolism. In the wheat grain is contained special chemical 

 constituents termed albuminoids, similar in composition to the white of 



