70 HORTICULTURAL SOCIETY OF NEW YORK. 



have not only the case of the wheat, but also the cases of plants, such as tropical fruits, 

 like the banana, that have been propagated for thousands of years from cuttings. Those 

 plants, with a strange uniformity, have declined in power of fertility. We ascribe that to 

 selection, with no explanation of how selection brought this about, apparently; but if we 

 ascribe it to inbreeding that seems ro me a much more satisfactory explanation. In the 

 case of wheat, of course, we have many other instances of that kind where plants have 

 adopted a habit of inbreeding. I think that in many cases this is misinterpreted. These 

 cases where inbreeding is common and frequent have been interpreted as universal cases. 

 I believe there is a great distinction between a cross-breeding now and then In several 

 generations, and a continuous and universal inbreeding. To what extent plants uniformly 

 and continuously inbreed, I think is a question still open for discussion. However, 

 supposing that that has become common and uniform, that fact, I believe, removes the 

 wheat from the class of normal plants and those that are making good evolutionary 

 progress, and places it alongside those that, like the banana, no longer produce seed, but 

 vary, and their condition is no longer one of species, but of a mere fan-shaped divergence 

 accompanied bj' very slight evolutionary progress. They are no longer bound together 

 as species; they have abandoned that proposition. In other words, normal inbreeding, 

 normal close-breeding, as in the case of wheat, would be a phenomenon to be associated 

 with a sexual propagation, with parthenogenesis, and with other types of a sexual re- 

 production. 



The Chair. I think the question of Professor Bateson is one in which we are all 

 interested. It is this: Can Professor Cook give any definite test, specific test, that will 

 cause a plant to be classed as a debilitated or a progressive variation? 



O. F. Cook: Just in that form I do not consider the question a fair one. That 

 is, the proposition is this: I have made the statement that there is such a relation between 

 the inbreeding and the relative sterility, and the question is whether evolutionists, wheat 

 breeders and otherwise, find that this relation holds good. If they do, why my whole 

 contention is justified. It is not a question of test; it is a question of observation, and if 

 the phenomena bears that interpretation, why, then, I think it may be a means of 

 progress to make that observation. 



D. T. MacDougal : I regret to say that I cannot find myself in accord with Mr. Cook 

 in his statement concerning De Vries' mutation of species. I have been in rather close 

 correspondence with Professor De Vries, and I am quite sure that Professor Cook is 

 mistaken when he says that mutation species are sterile. On the other hand, there have 

 been twelve species originated by mutation, and some of those are sterile and some are 

 fertile, and this very mutation of species has produced more sterile and more fertile 

 species. Now, as to general debility, whatever that may be taken to mean, I am quite sure 

 that this debility does not show in the vegetative part of the plant. I have specimens grow- 

 ing in the houses of the New York Botanical Garden, and these forms may be exhibited 

 to you to-morrow if you like, five of De Vries' miitation species, together with some of 

 the original stock, and so far as the vigor — also a general expression which may mean 

 a lot of things — so far as the vigor and general appearance of the mutation species are 

 concerned, they are quite as strong in every way as the parent. I am not sure how far 

 this affects Professor Cook's paper, and I find his entire paper rather significant and quite 

 interesting. It is quite apropos that I should receive this morning a letter from Pro- 

 fessor Dc ^'ries, dated the 20th of September, in which he speaks of his mutation experi- 

 ments with CEnothera cruciata, a narrow-petaled form from the Adirondacks, which he 

 has had under cultivation for some time. lie writes to ask me if certain changes ever 

 take place in this plant in America. I have just consulted with Dr. Britton, who, per- 

 haps, has studied this plant as thoroughly and as long as any man in the country, and 

 Dr. Britton tells me that he has never seen these changes, and so far as he knows they 

 do not occur in this country. This, therefore, I think, justifies me in announcing at this 

 time that Professor De Vries has succeeded also in obtaining a mutation species in 

 CEncthera. 



W. Fawcett: I did not understand Professor Cook's statements about coffee and the 

 effects that breeding might have upon the increase of the size of the berry. Nothing 

 whatever has been done in the West Indies in that direction, and I think probably that 

 is tl'.e reason why the coffee has been so full of vigor and less liable to disease than in 

 some other parts, like Ceylon. But the plan of getting young coffee crops is this: During 

 3 great part of the year the crop does not pay to pick. There are always some ripe ber- 



