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since John Hunter wrote his celebrated work ' On the 

 Nature of the Blood,' etc. New growths, to Hunter, 

 depended on an exudation of the plasma of the blood, 

 in which, by virtue of its own plasticity, vessels formed, 

 and conditioned the further progress. The influence of 

 these ideas seems to have still acted, even after a con- 

 ception of the cell was arrived at. For starting element, 

 Schleiden required an intracellular plasma, and Schwann 

 a structureless exudation, in which minute granules, if 

 not indeed already pre- existent, formed, and by aggre- 

 gation grew into nuclei, round which singly the produc- 

 tion of a membrane at length enclosed a cell. It was 

 then that, in this connection, we heard of the terms 

 blastema and cyto-blastema. The theory of the vege- 

 table cell was completed earlier than that of the animal 

 one. Completion of this latter, again, seems to have 

 been first effected by Schwann, after Miiller had insisted 

 on the analogy between animal and vegetable tissue, 

 and Valentin had demonstrated a nucleus in the animal 

 cell, as previously Brown in the vegetable one. But 

 assuming Schwann's labor, and what surrounded it, to 

 have been a first stage, the wonderful ability of Virchow 

 may be said to have raised the theory of the cell fully 

 to a second stage. Now, of this second stage, it is the 

 dissolution or resolution that has led to the emergence 

 of the word Protoplasm. 



The body, to Virchow, constituted a free state of in- 

 dividual subjects, with equal rights but unequal capaci- 

 ties. These were the cells, which consisted each of 

 an enclosing membrane, and an enclosed nucleus with 

 surrounding intracellular matrix or matter. These 

 cells, further, propagated themselves, chiefly by partition 

 or division ; and the fundamental principle of the whole 



