424 PRIMARY FACTORS OF ORGANIC EVOLUTION. 



single one who questions it, and I fail to find even so 

 much as an intimation of any such belief. All the 

 recorded observations founded upon actual practice 

 appear to point the other way, and consequently the 

 fact of partial transmission is assumed. 



" The practical value given to this factor is now 

 much smaller than formerly given, but that it is a fac- 

 tor of some value is universally assumed. 



' ' During the last century, and early part of this, 

 many graziers had a maxim that in the profitable pro- 

 duction of animals for slaughter, ' feed is more than 

 breed,' but now both breeders and graziers know that 

 heredity or 'breed,' is the more important. But no 

 breeder claims that a breed is or can be kept up to 

 extra size by selection alone. This belief is so uni- 

 versal, and is apparently so grounded upon long and 

 extensive experience, that I cannot find there has ever 

 been an attempt to increase the size of any breed with- 

 out special attention to this factor, and consequently 

 conclusive and direct experiment is entirely wanting. 

 Positive proof either way cannot be deduced from the 

 actual experiments of breeders ; their belief that feed 

 as well as selection is necessary, is a deduction from 

 the observation of many facts which bear upon the 

 question. 



" In this connection it must be borne in mind that 

 all the best breeders recognize the rule laid down by 

 Darwin, that those characters are transmitted with 

 most persistency which have been handed down 

 through the longest line of ancestry. Breeders do not 

 believe that the characters acquired through the feed- 

 ing of a single ancestor, or generation of ancestors, 

 can oppose more than a slight resistance to that force 

 of heredity which has been accumulated through many 



