PROTOPLASM 



that even the powerful microscopes which the ad- 

 vanced technical perfection of our time has pro- 

 duced, cannot show any more minute morphological 

 details in protoplasm than some very small dark 

 granules or scarcely visible drops of liquid, spoken 

 of as Microsomes. But the exact and extremely 

 regular development in the evolution of the cell 

 organs, as well as the undoubted co-operation of 

 protoplasm and the nucleus in cell cleavage and 

 in fecundation, is the strongest affirmation of the 

 organ-theory of protoplasm. In consequence of 

 these facts, we prefer to speak of Cytoplasm in- 

 stead of protoplasm, when we characterise the 

 living substance of the cell, surrounding the 

 nucleus. 



Experiment, too, seems to establish such a theory 

 very readily. When animal or plant tissue is 

 minutely pounded in a mortar, the pulpy mass 

 which we finally obtain is far from being an 

 organ, or from containing living cells. It is as 

 little a living thing as a watch remains 

 a watch after having been ground down to 

 powder. Notwithstanding this, the component 

 substances must have remained in either case. 

 It is clear that protoplasm is as little identical 

 with its component substances, for instance, 

 protein bodies, carbohydrates, etc., as pulverised 

 gold, steel, and rubies are identical with the 

 mechanism of a watch. This consideration must 

 lead us to the conclusion that protoplasm is not a 

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