•322 LIFE AND DEATH. 



the possession of a specific form acquired, preserved, 

 and repaired by the element. The fourth character, 

 and perhaps the most essential of all, is the property 

 of growth or nutrition with its consequence, namely, a 

 relation of exchanges with the external medium, 

 exchanges in which oxygen plays considerable part. 

 Finally, there is a last property, that of reproduction, 

 which in a certain measure is a necessary consequence 

 of the preceding, — i.e., of growth. 



These five vital characters of the elements are most 

 in evidence in cells living in isolation, in microscopical 

 beings formed of a single cell, protophytes and 

 protozoa. But we find them also in the associations 

 formed by the cells among one another — i.e., in 

 ordinary plants and animals, multicellular complexes, 

 called for this reason metaphytes and metazoa. Free 

 or associated, the anatomical elements behave in the 

 same way — feed, grow, breathe, digest in the same 

 manner. As a matter of fact, the grouping of the 

 cells, the relations, proximity and contiguity, which 

 they assume, introduce some variants into the ex- 

 pression of the common phenomena ; but these slight 

 differences cannot disguise the essential community 

 of the vital processes. 



The majority of physiologists, following Claude 

 Bernard, admit as valent and convincing the proof that 

 the illustrious experimenter furnished of this unity 

 of the vital processes. There are, however, a few 

 voices crying in the wilderness. M. Le Dantec is one. 

 In his new theory of life he amplifies and exalts the 

 differences which exist between the elementary life of 

 the proteids and the associated life of the metazoa. 

 In them he can see nothing but contrasts and 

 deviations. 



