222 HO"W CKOPS GROW. 



tinguishing their life, and by whose expansion or multipli- 

 cation all growth takes place. Then will follow an account 

 of the complex parts of the plant — ^its Compound Organs 

 — which are built up by the juxtaposition of numerous 

 cells. Of these we have one class, tIz. : the Roots, Stems, 

 and Leaves, whose office is to sustain and nourish the Indi- 

 vidual Plant. These may be distinguished as the Vege- 

 tative Organs. The other class, comprising the Flower 

 and Fruit, are not essential to the existence of the individ- 

 ual, but their function is to maintain the Race. They are 

 ^the Heproductive Organs. 



CHAPTER n. 



THE PRIMARY ELEMENTS OP ORGANIC STRUCTURE. 



§ 1- 

 THE YEGETABLE CELL. 



One of the most interesting discoveries that the micro- 

 scope has revealed, is, that all organized matter originates 

 in the form of minute vesicles or cells. If we examine by 

 the microscope a seed or an egg, we find nothing but a 

 cell-sti'ucture — an assemblage of little globular bags or 

 vesicles, lying closely together, anJ more or less filled 

 with solid or liquid matters. From these cells, then, comes 

 the frame or structure of the plant, or of the animal. In 

 the process of maturing, the original vesicles are often 

 greatly modified in shape and appearance, to suit various 

 purposes; but still, it is always easy, especially in the 

 plant, to find cells of the same essential characters as those 

 occurring in the seed. 



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