DIVISION III. 



LIFE OP THE PLANT. 



CHAPTER I. 



GERMINATION. 



§1- 



INTKODUCTORT. 



Having traced the composition of vegetation from its 

 ultimate elements to the proximate organic compounds, 

 and studied its structure in the simple cell as well as in 

 the' most highly-developed plant, and, as far as needful, 

 explained the characters and functions of its various 

 organs, we approach the subject of Vegetable Life 

 and NuTEiTiON, and are ready to inquire how the plant 

 increases in bulk and weight and produces starch, sugar, 

 oil, albuminoids, etc., which constitute directly or in- 

 directly almost the entire food of animals. 



The beginning of the agricultural plant is in the 

 flower, at the moment of fertilization by the action of a 

 pollen tube on the contents of the embryo-sack. Each 

 embryo whose development is thus ensured is a plant in 

 miniature, or rather an organism that is capable, under 

 proper circumstances, of unfolding into a plant. 



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