Text-book of botany : morphological and physiological / by Julius Sachs ; translated and annotated by Alfred W. Bennett ; assisted by W.T. Thiselton Dyer.
- Date:
- 1875
Licence: Public Domain Mark
Credit: Text-book of botany : morphological and physiological / by Julius Sachs ; translated and annotated by Alfred W. Bennett ; assisted by W.T. Thiselton Dyer. Source: Wellcome Collection.
Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.
836/880 page 820
![The characteristics of the parent-forms are as a rule so transmitted to the hybrid that the influence of both is manifested in all its characters, producing a fusion of the different peculiarities. This is more evident in the species- than in the variety-hybrids ; in the latter some of the non-essential characters of the parents sometimes present themselves in the offspring uncombined side by side; e. g. various kinds of streaks and blotches instead of a mixing of the colours of the flowers. Thus a hybrid which Sageret obtained from Cucumis Chale (female) with C. Melo Canta- lupus (which had a reticulated flesh) had a yellow flesh, a reticulate marking of the rind and moderately prominent ribs like the male parent, but white seeds and an acid flavour like the female parent. Another hybrid from the same species had, on the contrary, the sweet flavour and yellow flesh of the male, with the white seeds and smooth rind of the female parent. To this category belongs also the hybrid of Cytisus Laburnum and purpureus [known as Cytisus Adami], some of the branches of which partially or entirely resembled one and some of them the other parent-form. I have found what seemed to be a hybrid Antirrhinum majus, in which the inflor- escence bore on one side of the axis only dark-red, on the other side only yellow flowers, while between the two halves stood a single flower which was half red and half yellow. In addition to its inherited properties, the hybrid usually possesses characters of its own by which it is distinguished from both its parent-forms. One of these new characters, which occurs especially with variety-hybrids, is the tendency to vary more strongly than its parent-forms. Species-hybrids are usually weak in their sexual properties; those derived from nearly related parent-species are, on the other hand, more vigorous in their growth than their parent-forms, while hybrids resulting from the union of species less nearly related are generally feebler in their development. The luxuriant growth of the hybrids from nearly allied species is displayed in their taller and stouter stems, more copious root-system, and larger number of shoots (stolons, scions, &c.). Hybrids have also a tendency to a longer duration of life ; those of annual or biennial parent-forms often live a number of years, probably in consequence of their producing a smaller number of seeds. Hybrids are also characterised by commencing to flower earlier, and continuing to do so longer and more abundantly, than the parent-forms; sometimes they produce an extraordinary number of flowers, which are also larger, more enduring, and of brighter colour and stronger odour. They have also a tendency to become double, their staminal and carpellary leaves to increase in number and develope into petals. Along with this luxuriant vegetative growth, the sexual organs are usually weak, and this in every possible degree. ‘ The stamens,’ says Nageli, ‘ are, it is true, in some cases perfect externally, but partially or altogether infertile, the pollen-grains not attaining their proper development; while in others the stamens are altogether abortive and reduced to rudiments. The pistils (gynseceum) of hybrids are in most cases not distinguish- able externally from those of the parent species, but their ovules have no power, or only to a slight degree, of becoming fertilised; no embryonic vesicles are formed, or the embryo which begins to be developed from the embryonic vesicles perishes sooner or later. Under favourable circumstances, when fertile seeds are produced, their number is smaller, and they manifest a certain degree of feebleness in their slow germination and the short duration of this capacity.’ The feebleness of the sexual](https://iiif.wellcomecollection.org/image/b21981437_0836.jp2/full/800%2C/0/default.jpg)
