Inheritance Materials of Germ-Cells 83 



Advantages of Conceiving Germ-Cell Chromosomes as Initia- 

 tors in Hereditary/ Development 



This chemical way of viewing chromatin and chromosomes 

 sanctions the idea that these are to be regarded as initiators 

 of developmental processes which lead to hereditary attri- 

 butes, rather than determiners of those attributes. If one 

 wants to know in what way this conception would liave 

 an advantage over the determiner conception as a working 

 hypothesis, my reply is that the advantage is two-fold. 

 First, it would surely correct the tendency of genetic re- 

 search under the guidance of the determiner hypothesis, to 

 restrict its attention to attributes of adults at one end of 

 the ontogenic series and to the chromosomes of the germ- 

 cells at the other end, and to ignore or touch only in the 

 lightest way all the intervening parts of the series. This 

 correction would result because the new standpoint would 

 bring the whole series of continuities and transformations 

 alike into proper perspective, revealing thus that the mem- 

 bers of the series intervening between germ and adult must 

 be investigated in exactly the same way and with the same 

 objects in view as the end members, if complete understand- 

 ing of the hereditary process be the goal of research. It 

 could not then happen that the egg-cell would be repre- 

 sented, as it now so commonly is, as a relatively large sac 

 containing nothing significant for heredity except the rela- 

 tively small chromosomes. Nor could nearly the whole 

 mass of ontogenic phenomena, especially those of histo- 

 genesis, be treated so lightly in speculation and so largely 

 neglected in investigation as they have })een under the 

 domination of the determiner theory. 



The second advantage in the initiator conception is tliat 

 since it would recognize the "differential factor" of tin- 

 chromosomes to be in reality due to the fact that the wliole 

 ontogenic series to which the chromosomes belong is dilfLr- 



