The Orchid Review, 9: 103 (1901)

FERTILITY OF HYBRIDS
E. O. Orpet

In a recent discussion the question of the fertility of mules, or hybrids, was raised, the impression among some being that all true mules were sterile; should they prove fertile, it was argued to mean that hybridity was not present, even though so-called bigeners. The discussion arose owing to the statement that our experience had proved that parents of hybrid origin were more fertile than mere varieties, or even species, in the production of their kind. Take Epidendrum X O'Brienianum as an example. We have succeeded in raising from and through it many crosses; Cattleya amethystoglosssa when fertilised with it gives us a fine Epicattleya; with Sophronitis, it gives us hundreds of seedling Epiphronitis now in bud; when crossed with Cattleya X Claesiana it produced myriads of plants; and so on, seemingly because of its hybrid origin; whereas, Epidendrum. radicans and E. cinnabarinum have never yet given us a pod, though tried times without number.

We could name other cases, but this will suffice. The question raised is as to whether E. X O'Brienianum is a true mule, and we would be glad to get the opinion of the Editor and others in this connection. There seems to be quite a little confusion among cultivators as to what is a hybrid and what is a cross. Taking any of the Cattleya labiata varieties, such as C. Mendelii and C. Mossise, and raising seedlings between them would not give hybrids, we take it, but mere crosses; but, were that section mated with any of the two-leaved species, such as C. Bowringiana or C. guttata, would the progeny be regarded as hybrids?

We have proved, or come so near proving, that many true species are impotent, in that we cannot get results by their use, but have, so far, not noticed that any Orchid of garden origin fails us in this respect. We have in flower now over a dozen Epidendrums, with many more in bud, as the result of crossing E. X O'Brienianum with E. radicans and E. cinnabarinum; all except one have the lax flower spike traceable to E. evectum; all are decorative enough to be worth growing, and are of better habit than the sprawling E. X O'Brienianum, but only one is an improvement on any of the kinds connected with its origin, and, strange to say, all the segments of the flowers are spotted with dark red over a rich scarlet ground, with a compact head of flowers like E. radicans. We find that these reed-like plants can be made to bear seed and flower within two years from crossing, and it would be a very interesting pastime could we give space to it.

E. O. Orpet.
S. Lancaster, Mass., U.S.A.

[WE should say that all seedlings raised by the intercrossing of distinct species are true hybrids. Many such plants are now known to be fertile, and this supposed test fails. There is room for difference of opinion in some cases as to what constitutes a species, but we do not consider Cattleya Mossiae and C. Mendelii as simply varieties of C. labiata. At the very least they are well-marked geographical sub-species, having their own characters, and their own varieties. This question was exhaustively discussed at pages 266-270 of our third volume. There can be no question as to the distinctness of Epidendrum evectum from E. radicans, and consequently none that E. X O'Brienianum is a true hybrid. The question of its fertility is interesting, and on this point evidence is fortunately accumulating. It is certainly remarkable to find that seedlings can be got to flower within two years from crossing, and we should like to have complete details on this point.—Ed.]

See Hurst for more bigeneric orchid hybrids