DIVISION III. 



LIFE OF THE PLANT. 



CHAPTER L 



GERMINATION. 



w JL 

 INTRODUCTORY. 



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, explain- 

 ed the characters and functions of its various organs, we 

 approach the subject of VEGETABLE LIFE and NUTRITION, 

 and are ready to inquire how the plant increases in bulk and 

 weight and produces starch, sugar, oil, albuminoids, etc., 

 which constitute directly or indirectly almost the entire 

 food of animals. 



The beginning of the individual plant is in the seed, 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 circum- 

 stances, of unfolding into a plant. 

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