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Updated: June 14, 2025
Since that time, however, the natural distribution and the cultural history of Oenothera has been very thoroughly worked out. Oenothera Lamarckiana is the common Evening Primrose of English gardens.
Concerning inheritance of these characteristics nothing can be directly asserted because of the lack of pollen. The new type can only be perpetuated by crosses, either with the parent form or some other mutant. I have fertilized it, as a rule, with lamarckiana pollen, but have often also used that from nanella and others. In doing so, the lata repeats its character in part of its offspring.
He found a large number of specimens of Oenothera Lamarckiana growing in an abandoned potato-field at Hilversum, and these plants showed an unusual amount of variation. He transplanted nine young plants to the Botanic Garden of Amsterdam, and cultivated them and their descendants for seven generations in one experiment. Similar experiments have been made by himself and others.
Some plants give about one-third scintillans and two-thirds lamarckiana, while the progeny of individuals of another strain show exactly the reverse proportion. Two points deserve to be noticed. First the progeny of the scintillans appears to be mutable in a large degree, exceeding even the lamarckiana.
This first stage is called the 'rosette. From the reduced stem are afterwards developed one or more long stems with elongated internodes, bearing leaves and flowers. In the mutation lata the rosette leaves are shorter and more crinkled than those of Lamarckiana, and the tips of the leaves are very broad and rounded.
On the other hand, gigas and rubrinervis, oblonga and albida obviously bear the characters of progressive elementary species. They are not differentiated from lamarckiana by one or two main features. They diverge from it in nearly all organs, and in all in a definite though small degree.
Many of them contain no good seeds at all; from others I have succeeded in saving only a hundred seeds from thousands of capsules. These seeds, if purely pollinated, and with the exclusion of the visits of insects, reproduce the variety, entirely and without any reversion to the lamarckiana type. Correlated with the detailed structures is the form of the flower-buds.
In the OEnothera gigas the rosette leaves are broadly lanceolate with obtuse or rounded tips, more crinkled than in Lamarckiana, petioles shorter. The stem-leaves are also larger, broader, thicker, more obtuse, and more crinkled than in Lamarckiana. The stem is much stouter, almost double as thick, but not taller because the upper internodes are shorter and less numerous.
If this were true, all chance of ever seeing a new species arise would be hopelessly small. Fortunately the evening-primroses exhibit contrary tendencies. One of the great points of pedigree-culture is the fact that the ancestors of every mutant have been controlled and recorded. Those of the last year have seven generations of known lamarckiana parents preceding them.
However, it would be of great interest to ascertain whether O. lamarckiana yet grows in America, and whether it is in the same state of mutability here as it is in Holland.
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