18S LUTHER BURBANK 



Cil raiulU. For they lenre to emphatiie a fpnpat 

 ftUKUniefital tnith of beredit>% which bis • more 

 imporUiit bearing on the problemt of racial 

 de%'eIopment of all orgajiie bein^ including 

 man himielf. It haa become more and more 

 clear in recent years that the widerl>nng prin- 

 ciplet of erolution apply to plants and animals 

 alike, and that much may be learned about the 

 better breeding of mankind from a direct study 

 of the breeding of the lower organisms. 



And as regards the particular case mider con- 

 sideration, it u scarcely to be doubted that we 

 may draw important lessons from the obvious 

 results of the hybridizing of plants to spply to 

 the commingling of human races. 



It is commonly held that the various existing 

 races of man constitute a single species. But 

 this classification was msde under the influence 

 of the old idea that sterility of offspring is a valid 

 test of specific difi*erence. No one nowadays 

 holds that view, with regard to plants at any 

 rate, and the view is probably no more valid in 

 its applieation to a great number of animals, in- 

 cluding man himself. 



But, in any event, the question as to whether 

 mankind constitutes a single species or several 

 species is a matter of definition of no real impor- 

 tance. It is beyond question that the human 



