The Organism and its Major Parts 33 



The kernel of the difficulty arising from the complex make- 

 up lies in the fact, emphasized by recent investigations, espe- 

 cially those on regeneration, that in very many animals and 

 plants, when the individual is artificially divided, parts of 

 individuals have remarkable powers of independent life, even 

 to the extent of reconstituting themselves into other indi- 

 viduals as perfect as the one that was divided. The reason- 

 ing from these facts is, essentially, that because a given in- 

 dividual may divide or be divided artificially into two or 

 more parts, which may in turn develop into other individuals 

 like the original, the original was therefore not a single in- 

 dividual. In other words, individuality is denied these or- 

 ganisms because of what parts of them can do when severed 

 from the whole. The unity, the integrity of the individual 

 is called in question, not on account of what it is here and 

 now, but on account of what the parts may do after they 

 have been severed, naturally or artificially, from the original 

 unity. 



No biologist, and especially no organismal biologist, would 

 minimize the significance of the fact that the severed parts 

 of many organisms possess such remarkable reconstitutive 

 powers. The organismal biologist, I assert, is especially 

 interested in the phenomena because they are to him unique 

 and unanticipated evidence favorable to his general stand- 

 point. What he denies is that the phenomena count a scin- 

 tilla against the reality and essentiality of the individual. 

 He points out that their importance, so far as the prob- 

 lem of individuality is concerned, is not that they show much 

 about the ultimate nature of the individual's unity, but that 

 they do show much about the degree of that unity. 



The Individual Plant and Its Parts 



The purposes of this chapter will be best served by de- 

 voting a section to examining a few efforts which have been 



