(President Morris then took the chair.)
The Chairman: Please let me add that the hickory pumpkin idea is not to be taken seriously. That is a highly speculative proposition. I have found some times that, in a very scientific audience, men who were trained in methods of science, had very little selvage of humor,—little margin for any pleasantry, but this highly speculative suggestion, curiously enough, is not in fact more speculative than would have been the idea twelve years ago that you could hatch an egg, start an egg to development—without fertilization.
Mr. Hutt: I would like to ask how widely you have been able to cross species?
The Chairman: It has been possible to cross species of hazels freely with the four species that I have used, the American hazel, Corylus Americana; the beak hazel, Corylus rostrata; the Asiatic, Corylus colurna, and Corylus pontica. These apparently cross readily back and forth. With the hickories I think rather free hybridization occurs back and forth among all, but particularly in relation to groups. The open-bud hickories, comprising the pecan, the bitternut, the water hickory, and the nutmeg hickory, apparently, from my experiments, cross much more readily among each other than they cross with the scale-bud hickories. The scale-bud hickories appear to cross much more freely among each other than they cross with the open-bud hickories; not only species but genera may be crossed, and I find that the walnuts apparently cross freely with the open-bud hickories and the open-bud hickories cross with the walnuts. I have thirty-two crosses between the bitternut hickory and our common butternut, growing. All of the walnuts apparently cross rather freely back and forth with each other. I have not secured fertile nuts between the oaks and chestnuts, but I believe that we may get fertile nuts eventually. The nuts fill well upon these two trees fertilized with each others' pollen respectively, but I have not as yet secured fertile ones. We shall find some fertile crosses I think between oaks and chestnuts, when enough species have been tried.
Mr. Hutt: Do you notice any difference in the shapes of any of those hybrids, the nuts, when you get them matured and harvested? Do they look any different from the other nuts on the tree?
The Chairman: There isn't very much difference, but I seem to think that sometimes the pollen has exercised an influence upon the nuts of the year. Theoretically it should not do so, but I noticed one case apparently in which I crossed a chinkapin with a Chinese chestnut, and the nuts of that year seemed to me to present some of the Chinese chestnuts' characteristics.
Mr. Hutt: This year I crossed a number of varieties of pecans and in nearly all those crosses there was to me quite an evident difference in the nuts. For instance those gathered off certain parts of a pecan tree of certain varieties, Schley or Curtis or Frotscher, would be typical nuts, but those hybrids or crosses that I produced were distorted, more or less misshapen and seemed to have peculiarities; so that when we came to look over the colony we were in doubt whether they were hand pollinated hybrids or had been pollinated before we got the blossoms covered. Many of them evidenced a great number of distortions, and one of them I remember particularly whose shell was so thin it was just like a piece of brown paper; and there were several peculiarities that were quite noticeable in those hand pollinated nuts.
The Chairman: That is a very interesting point. When we come to consider deformities of nuts we shall find very many cases due to the character of the pollinization. I crossed the Persian walnut with the shagbark hickory and had nuts that year of just the sort of which Mr. Hunt speaks, with shells as thin as paper. One could crush them with the very slightest pressure of the finger. The shells were not well developed. Unfortunately the mice happened to get at all of those nuts. I don't know if they were fertile or not. The kernels were only about half developed. I should look for deformity in these nuts rather than a taking on of the type of one parent over the other, the idea being based on theoretical biological considerations. We had last year a photograph of a tree in California which apparently was a cross, a very odd cross—does any one remember about that California tree?
Mr. Wilcox: It was a cross between Juglans Californica and the live oak.
The Chairman: Both the foliage and the nuts were very remarkable and pertained to characters of these two trees. Such a cross to my mind would be wholly unexplainable excepting on the ground recently brought out by Loeb and his followers in crossing the lower forms of animal life and finding that the cell membrane of the egg, if destroyed, will allow of very wide fertilization subsequently with other species. It occurs to me now—I had no explanation last year, but it occurs to me now, knowing of Loeb's experiments—that it is possible that one of the parents, the parent California oak tree carrying the female flowers, might have had its sex cells subjected to some peculiar influence like acid, sulphurous acid, for instance, from some nearby chimney. Sulphurous acid perhaps from someone merely lighting a match to light a cigar under the tree; he might have so sensitized a few female flowers, may have so injured the cell membrane of a few female germ cells that cross pollinization then took place from a walnut tree. It is only on some such ground as the findings of Loeb that we can explain such a very unusual hybridization as that, which appeared to me a valid one, of a cross between an oak and a walnut.