Introductory Remarks 7 



of disharmonies, the rest are doomed on account of a 

 gross lack of harmony of the parts. These latter we 

 never see and this gives us the erroneous conception 

 that harmony or "design' is a general character of 

 living matter. If anybody wishes to call the non- 

 viability of 99nf per cent, of possible teleosts a pro- 

 cess of weeding out by "natural selection* we shall 

 raise no objection, but only wish to point out that our 

 way of explaining the lack of design in living nature 

 would be valid even if there were no theory of evolu- 

 tion or if there had never been any evolution. 



3. v. Uexkull is perfectly right in connecting 

 the problem of design in an organism with Mendelian 

 heredity. The work on Mendelian heredity has shown 

 that an extremely large number of independently 

 transmissible Mendelian factors help to shape the 

 individual. It is not yet proven that the organism 

 is nothing but a mosaic of Mendelian factors, but no 

 writer can be blamed for considering such a possibility. 

 If we assume that the organism is nothing but a mosaic 

 of Mendelian characters it is difficult indeed to under- 

 stand how they can force each other into a harmonious 

 whole 1 ; even if we make ample allowance for the law 



1 This difficulty is also felt by mechanistic writers like Child, who 

 on page 12 of his recent book on Senescence and Rejuvenescence 

 (Chicago, 1915) makes the following remarks: "These theories of Weis- 

 mann do not account satisfactorily for the peculiarly constant course 

 and character of development and morphogenesis. If we follow them 

 to their logical conclusion, which their authors have not done, we find 

 ourselves forced to assume the existence of some sort of controlling and 



