PROFESSOR WEISM 'ANN'S THEORIES. 473 



PROFESSOR WEISMANN'S THEORIES.* 



By HEEBEET SBENCEE. 



APART from those more special theories of Prof. Weismann I 

 lately dealt with, the wide acceptance of which by the bio- 

 logical world greatly surprises me, there are certain more general 

 theories of his — fundamental theories — the acceptance of which 

 surprises me still more. Of the two on which rests the vast super- 

 structure of his speculation, the first concerns the distinction be- 

 tween the reproductive elements of each organism and the non- 

 reproductive elements. He says : 



"Let us now consider how it happened that the multicellular animals and 

 plants, which arose from unicellular forms of life, came to lose this power of living 

 forever. 



" The answer to this question is closely bonnd up with the principle of divi- 

 sion of labor which appeared among multicellular organisms at a very early 

 stage. . . . 



" The first multicellular organism was probably a cluster of similar cell?, but 

 these nnits soon lost their original homogeneity. As the result of mere relative 

 position, some of the cells were especially fitted to provide for the nutrition of the 

 colony, while others undertook the work of reproduction " (Essays upon Heredity, 

 p. 27). 



Here, then, we have the great principle of the division of labor, 

 which is the principle of all organization, taken as primarily illus- 

 trated in the division between the reproductive cells and the non- 

 reproductive or somatic cells — the cells devoted to the continuance 

 of the species, and the cells which subserve the life of the indi- 

 vidual. And the early separation of reproductive cells from 

 somatic cells, is alleged on the ground that this primary division 

 of labor is that which arises between elements devoted to species- 

 life and elements devoted to individual life. Let us not be content 

 with words but look at the facts. 



When Milne-Edwards first used the phrase "physiological 

 division of labor," he was obviously led to do so by perceiving the 

 analogy between the division of labor in a society, as described by 

 political economists, and the division of labor in an organism. 

 Every one who reads has been familiarized with the first as illus- 

 trated in the early stages, when men were warriors while the cul- 

 tivation and drudgery were done by slaves and women ; and as 

 illustrated in the later stages, when not only are agriculture and 

 manufactures carried on by separate classes, but agriculture is 

 carried on by landlords, farmers, and laborers, while manufac- 

 tures, multitudinous in their kinds, severally involve the actions 



* A postscript to the essay on The Inadequacy of " Natural Selection." 



