MORPHOLOGICAL UNITY OF LIVING BEINGS. 167 



of Haeckel, the idioblasts of Hertwig, the pangenes of 

 de Vries, the plasomes of Wiesner, the gemmules of 

 Darwin, and the biophores of Weismann. 



Biologists who have not got all that they hoped 

 from microscopic structure are therefore thrown back 

 on hyper-microscopic structure. 



It is very remarkable that all this profound know- 

 ledge of structure has been so sterile from the point 

 of view of the knowledge of cellular functional activity. 

 All that is known of the life of the cell has been 

 revealed by experiment. Nothing has resulted from 

 microscopic observation but ideas as to configuration. 

 When it is a question of giving or imagining an 

 explanation of vital facts, of heredity, etc., biologists 

 unable to supply anything beyond the details of 

 structure revealed by anatomy have had recourse to 

 hypothetical elements, gemmules, pangenes, bio- 

 phores, and different kinds of determinants. 



Anatomy never has explained and never will ex- 

 plain anything. "Happy physicists!" wrote Loeb, 

 " in never having known the method of research by 

 sections and stainings ! What would have happened 

 if by chance a steam engine had fallen into the hands 

 of a histological physicist? How many thousands of 

 sections differently stained and unstained, how many 

 drawings, how many figures, would have been pro- 

 duced before they knew for certain that the machine 

 is an engine, and that it is used for transforming 

 heat into motion !" 



The study of physical properties, continued on 

 rational hypotheses, has also thrown some light 

 on the possible constitution of living matter. The 

 gap between microscopical structure and molecular or 

 chemical structure has thus been filled. 



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