Page:Popular Science Monthly Volume 33.djvu/759

Rh plants; or rather, the resulting new organism is the outcome of a compromise, perhaps even of a struggle for mastery, between all the parts or component elements of the two parent plants. Hence, in all species, animal or vegetable alike, the young on the whole tend to resemble both parents equally, but in different modes of combination, which give them each what we call individuality, and so make them really and truly new plants, not mere reissues of either parent form.

When I had written thus far on this present article, I laid down my pen for a little rest, and strolled out alone upon the dry African hill-side, a lower shoulder of the Atlas range, that stands opposite the villa whence I date these words. By a curious coincidence, as I rambled through the lentisk scrub, I happened to light upon a little bed of natural hybrid orchids, which so admirably illustrate the nature of this peculiar intermixture that I joyfully accepted them to point the moral with which I must close this long lay sermon. Numbers of a large and handsome yellow orchid grow on the slopes of that particular hill, and in and out among them spring members of another yet closely related species, dingier brown, and different in shape, disposition of parts, and general appearance. Some wandering bee, visiting a flower of the yellow orchid at this spot where I stood, had carried away on his head its gummy pollen-masses, and then, contrary to the common habit of bees (who generally visit only one particular species of plant at a time), had deposited them on the stigma of a neighboring brown specimen. I suppose he was a young and inexperienced insect, who had not yet learned to avoid the bad practice of mixing his honeys. From this chance fertilization any number of hybrids had taken their rise, all of them more or less resembling in certain respects both parents. In most cases they had, to a great extent, the distinctive shapes of the brown kind, with a preponderating amount of yellow color. But among them all they presented every possible intermediate type between the two parent forms. It seemed to me that this accidental find exactly fitted in with the subject of my paper. We see here how each embryo seed, separately impregnated by a pollen-grain from another plant, grows out with a tendency to reproduce both ancestral forms equally, and how the conflict between the two tendencies, both of which can not fully be realized, produces in the end an individual compromise—a something which is not quite either, but which combines in varying and incalculable degrees the strongest points of both.

Unless I mistake, we have here the solution (suggested in the main by Mr. Herbert Spencer) for one of the deepest and most fundamental problems of all life, animal or vegetable—the problem of reproduction, heredity, and individual variation.