EVOLUTION UNDER DOMESTICATION. 



73 



represent six botanical species; the fruits embody the blood, so to speak, of six distinct 

 types. 



W. H. Evans: Bearing out the remark of Dr. Morris, recently I got a report from 

 the Hawaiian Islands, and one of their most prolific varieties, and what they consider 

 their best coffee there, is what they call Horner's Guatemala, which is a variation from 

 the Guatemala coffee. It is being grown by Mr. Lewison, and he considers it not only 

 the most prolific, but it has the best flavor. 



O. F. Cook: Guatemala is an extremely favorable country for coffee culture. Their 

 coffee is magnificent, and that it should have greater vigor, etc., than other coffees from 

 some other regions that I have seen I can readily imagine. My contention in regard to 

 coffee was that, while coffee was an extremely uniform and stable plant as compared with 

 any wild species, yet when it did vary the variations were pronounced, and it was this 

 pronounced variation, accompanied by relative sterility, that I noted as the facts that I 

 wanted to bring into relation. In relation to the question of sterility, I thought I had 

 made it plain in my paper that this is a relative question. That is, Professor De Vries, 

 and I think Dr. MacDougal, will have to admit that the average fertility of nearly all 

 mutations is far below that of the parent, I think that is the case, and it is so repre- 

 sented by Professor De Vries himself. Then, furthermore, I have asked my evolutionary 

 breeding friends to produce a mutation or a sport so-called which exceeded the parent 

 in reproductive fertility. I am aware that the vegetative fertility or vigor is a matter that 

 is often very slightly conneced with the reproductive strength. We hav? that in the case 

 of the banana, for instance. That and other plants that have been in cultivation in the 

 tropics for a much longer time than other plants have been under cultivation have tended 

 very much to a lessening of the fertility from seeds. With reference to Mr. Fairchild's 

 question, I would say that I have associated those two facts, that is, the wide distribu- 

 tion of plants with recent evolutionary progress; and the subsequent segregation of species 

 among those plants is itself an indication that when those plants are crossed you restore 

 at once this greater species evolution, so to speak. At any rate, whatever would take 

 place in such plants would depend upon the divergence that had already been attained. 

 If the divergence is too great, then you would get even in those plants relatively sterile 

 hybrids. Of course, they may produce an extraordinary and much greater abundance of 

 fruit. 



