DARWINISM DEFENDED. 181 



'Because in each reducing division of the germ-cells their 

 ids are lessened by one-half, the possibility exists of gradu- 

 ally removing from the germ-plasm of the species the ids of 

 the disadvantageous variations, for in each generation the 

 offspring of the disadvantageous id combinations are ex- 

 tinguished [by selection], so that from generation to gen- 

 eration the germ-plasm gradually becomes purified of the 

 disadvantageous ids, while the favourable combinations 

 which amphimixis produces are retained, and there finally 

 remain only the advantageously varying combinations or, at 

 any rate, those in which the advantageously varying deter- 

 minants are in the majority and therefore have the most 

 influence' (Vol. II, p. 222). This conception of the sig- 

 nificance of the reduction divisions of the maturing germ- 

 cells and their fusion is very suggestive, and, theoretically, 

 there is little to be objected to in the idea that the differences 

 thus created can be used by personal selection for the pro- 

 duction of harmonious coadaptations. Indeed, with this 

 explanation in hand, it is obvious that the theory of germinal 

 selection is superfluous for the explanation of coadaptations 

 if we may assume that there is always a great mass of 

 material in the individual variations, for the possibility of 

 varying combinations of these requires no further expla- 

 nation." 



For the most part it is obvious that Plate, and with 



him other fair-minded Darwinians, recognise fully the 



Plate recog- cogency .of the objections against Darwinism 



nises the weight based on the inutility of slight variations, on 



of certain objec- i1 , . , , . . 



tions to Darwin- tne occurrence and persistence of hosts of 

 ism - trivial or indifferent species differences, and 



on the difficulties presented by the demands of a controlled 

 appearance of variations necessary to the development of 

 coadaptive structures and functions, so that they are inclined 

 to make the concessions which I have referred to in the 

 beginning (chapter vi) of this presentation of "Darwinism 



