The Organism and its Protoplasm 125 



the opposite; that is, it would have to be to the effect that 

 a dog would be strictly himself and as well off with a tree's 

 protoplasm as with his own sarcode. 



But the particular point I want to l)ring out is that, tak- 

 ing the utterances of not merely the fatlier but the fathers 

 of modern biology at their maturest and best, one finds 

 that not only did they not teach the identity of protoplasm 

 in all living beings, but that what they did teach was some- 

 thing very different. Ferdinand Cohn, for example, said of 

 the protoplasm which he saw escaping through the cell-wall 

 of the alga studied by him, "if not identical" with animal 

 sarcode, it "must be at any rate in the highest degree anal- 

 ogous" to it. ^^ 



Max Schnitzels Actual Teachings as to Protoplasm and 



Sarcode 



In 1861, after a great many trustworthy observations 

 had been made in widely separated portions of the organic 

 realm, of substances so closely resembling one another, came 

 ]Max Schultze with the essay which gained for him the widely 

 recognized title "the fatlicr of modern biology." Exactly 

 what did Schultze aim at in this essay .'^ He was primarily 

 concerned with the nature of the cell and not of the })roto- 

 plasm. The title chosen indicates this definitely enough: 

 "Concerning muscle corpuscles and that which has been* 

 named a Cell." What he undertook was to dis})ose of the 

 then prevalent doctrine that the cell-wall is the most essen- 

 tial part of the cell, by proving that tlie body itself, not 

 the skin or membrane of the cell, is tlie really important 

 thing; and partly by showing that even in cells having a dis- 

 tinct membrane, what is contained witliin it is similar to the 

 bodies of non-membranous cells and is the really active, 

 living part of the cell. His definition, "A cell is a little mass 

 of protoplasm in the interior of which lies a nucleus" ^^ epit- 



