Journal of the Royal Horticultural Society, Volume 24:337-338 (1900)

NOTES ON SOME HYBRIDS
Thomas Meehan, Germantown, Philadelphia, U.S.A.

My actual experience in hybridisation is interesting though not extensive. It began in my fourteenth year, and with the Fuchsia. My father was an excellent botanist, and a great lover of rare plants. The plant-house at St. Clare was not large, but friends frequently sent him cuttings of rare things and flowers of new introduction. Fuchsia fulgens had been introduced a year or so before, and someone sent my father a few flowers. I was the "garden boy" under my father. Fond of garden experiments, I had decided to repeat Knight's work in hybridising garden Peas, when the large amount of pollen on the Fuchsia flowers interested me. It was applied to the stigma of Fuchsia longiflora. From the one berry that resulted several dozen plants were raised. The largest and best of these subsequently appeared in the trade through the agency of Youell & Co., of Yarmouth, as 'St. Clare.' An interesting lesson followed. From this one berry no two of the many seedlings were alike. Some nearly approached the female, some the male; none could fairly be said to be intermediate. It was evident that the action of the pollen had not alone to do with the variation. Some physiological force, to this day not understood by me, must have been co-ordinate in the production of these results.

Subsequent to this I made an experiment with the Diplacus puniceus and D. glutinosus. These seedlings were all exactly intermediate in the colour of the flowers, a bright orange; but there were no other differences. From the orange colour I named them D. aurantiacus. Others must have experimented, and with the same result, for I do not think the one figured in the "Botanical Register" came from my stock.

My next experiment was some years later in America. Disemma aurantia, the female parent, and Passiflora coerulea, the male. To my surprise the progeny was simply the Disemma. There was no trace of the Passionflower in them. To an objection that might be made I will note that an intelligent hybridiser knows how to avoid the action of the plant's own pollen in experiments of this kind.

Some few years later I endeavoured to produce a new race of Fuchsias from F. arboresccns pollenised by garden hybrids. The seedlings both in foliage and flowers were F. arborescens and nothing more. To the objection that the pollen of a hybrid may have been impotent I may reply that these hybrids produce berries frequently with no pure species near them; and though I have not sown the seeds, I have heard of others raising plants from them. Moreover due precaution was taken to avoid the action of their own pollen.

In recent years I crossed a flower of Rosa Kamtschatica with pollen of 'General Jacqueminot.' Only two plants grew from the seeds in this one pod. One of these plants was exactly Rosa cinnamonea; the other had all the appearance of the 'General,' but was attacked so persistently by a parasitic fungus that, in spite of all effort, it died at the end of its second year, and before flowering.

These have been my most instructive experiments. What has been done with Geraniums and other florists' flowers has still been instructive in this, that hybrids are just as fertile, and the pollen just as potent, as in the original species. Barrenness occurs as often among individuals of pure species as among the progeny of individuals resulting from hybridisation. Sterility results from some physiological law, of which pollenisation is but an incident.

In regard to the supposed sterility of hybrids, Dr. Engelmann describes in his well-known paper on American Oaks a number of supposed hybrids in nature. In one case, Quercus palustris x imbricaria, he cites its sterility in evidence. Before the tree was destroyed by a railroad track he found a solitary acorn. This grew and is now a large tree on my grounds, and is of exceptional fertility, producing a large crop of acorns of pure Quercus palustris, and with the foliage and habit of the same species, though there are numerous leaves entire, as in imbricaria, but in venation and all other characters it is wholly Quercus palustris.

Though hybrids in nature are probable, we have little direct evidence of the fact. The occurrence of intermediate forms, or of sterility in some cases, is no evidence, especially when we know of the wide range of variation in such cases, for instance, as in monotypic species, where cross-pollenation is out of the question.