THE PROBLEM OF PATTERN 19 



vidual body possesses normally the full complement of 

 chromosomes, and therefore, supposedly, the complete 

 nuclear pattern of the fertilized egg. Nevertheless 

 different cells of the body become different and differ- 

 ent kinds of organismic correlation arise between them. 

 Boveri recognized this fact years ago and admitted 

 that local conditions rather than the nuclear pattern 

 must be responsible as activating factors for the origin 

 of these differences between the cells, but many biologists 

 have either not discussed the question or have failed to 

 recognize the fact that if all the cells are originally alike 

 they cannot of themselves become different. Loeb, in 

 his book The Organism as a Whole, evades the entire 

 problem with the statement that " the egg is the embryo 

 in the rough" and makes no attempt to show how the 

 egg has attained this condition, and Morgan in his 

 recent discussion of the organism as a whole (Morgan, 1 

 1919, pp. 241-46) fails completely to account for the 

 fact that cells, which are originally alike as regards 

 nuclear pattern, become different in a definite and 

 orderly way, and is very evidently helpless before the 

 problem of the organism as a whole. Moreover, even 

 if we maintain that a cytoplasmic pattern is determined 

 in the egg by the nuclear or chromosomal pattern and 

 that the pattern of the multicellular organism results 

 from the distribution of the components of the cyto- 

 plasmic pattern of the egg among different cells in 

 development, we have attained no solution but merely 

 a formulation of the problem of organismic pattern in 

 the purely preformistic terms of nuclear pattern, and 

 the problem of nuclear pattern remains. But there is 



1 For this and similar references, see the list on p. 273. 



