CHAPTER II. 



USE OF THE MICROSCOPE IN BOTANY. 



IT is almost impossible to exaggerate the value of the 

 microscope in vegetable physiology, and the amount 

 of information regarding the minute structure of plants 

 which has been obtained by this instrument. You 

 cannot, I think, do better than begin your microscopic 

 studies with some of the various forms of plant-life 

 that occur abundantly in our ponds, rivers, and 

 ditches. Many of these are of very simple construc- 

 tion, and you may proceed from the investigation of a 

 plant which has a separate existence as a single cell, 

 to that of such complex and highly differentiated 

 forms as the oak, the ash, and other mighty trees of 

 the field or forest. Now the microscope will reveal 

 to you the interesting fact that the origin of every 

 plant is a single cell. Dr. Carpenter has well said, 

 u The plan of organisation throughout the vegetable 

 kingdom presents this remarkable feature of uni- 

 formity that the fabric of the highest and most 

 complicated plants consists of nothing else than an 

 aggregation of the bodies termed cells, every one of 

 which, among the lowest and simplest forms of vege- 

 tation, may maintain an independent existence, and 

 may multiply itself almost indefinitely, so as to form 

 vast assemblages of similar bodies. And the essen- 

 tial difference between the plans of structure in the 

 two cases, lies in this : that the cells produced by the 

 self-multiplication of the primordial cell of the proto- 

 phyte, are all mere repetitions of it, and of one 

 another, each living by and Jor itself; whilst those 



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