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Updated: May 8, 2025
These investigations have led me to the conclusion, that atavism, as it is generally described, always or nearly always is due to hybridization, and therefore it is to be considered as untrue or false atavism. True atavism, or reversion caused by an innate latent tendency, seems to be very rare, and limited to such cases as we have spoken of under our last heading.
The inbreeding consequent upon this paucity of sponge life has produced a certain fixity of character in fresh-water sponges, and is in direct opposition to the effects of hybridization in the salt-water sponges, by which they have acquired the capacity of adapting themselves to local circumstances.
In dealing with this subject we must leave aside all questions concerning more remote relationships. It is not my purpose to treat of the doctrine of hybridization at any length. Experience is so rapidly increasing both in a practical and in a purely scientific direction that it would take an entire volume to give only a brief survey of the facts and of all the proposed theories.
De Vries' experiments in variation and Mendel's rediscovered work on plant hybridization had hopelessly undermined the older notion that the evolution or progress of species has taken place through the inheritance of acquired characters that is, that the individuals developed or adapted themselves to suit their surroundings and that these body-modifications were inherited by their offspring.
Is there any test of a physiological species? The usual answer of physiologists is in the affirmative. It is said that such a test is to be found in the phænomena of hybridization in the results of crossing races, as compared with the results of crossing species.
Thus it comes about that the hybridization of Lycastes has been attempted but recently, and none of the seedlings, so far as I can learn, have flowered. They have been obtained, however, in abundance, not only from direct crossing, but also from alliance with Zygopetalum, Anguloa, and Maxillaria.
Of these three firms one is extinct; the second has taken up, and made its own, the fascinating study of hybridization among orchids; the third still perseveres. Twenty years ago, nearly all the great nurserymen in London used to send out their travellers; but they have mostly dropped the practice. Correspondents forward a shipment from time to time.
Until such a community is organized sex instinct traffics freely across racial barriers; once organized, race instinct conquers or restrains hybridization. It is a right understanding of the conditions under which human instincts work that gives us the true key to the hybridization of Spaniard and American Indian.
In 1866, however, both the British and Dutch Indian Governments purchased small quantities of seed from Mr. Charles Ledger. From this seed the very valuable plantations of Java and Ceylon have been propagated. I have already described the method of cultivating Cinchona Ledgeriana adopted by the planters, and how advantage is taken of the extreme liability of the cinchona plant to hybridization.
Burbidge has suggested that "some one" who takes an interest in orchids should establish a farm, a plantation, here and there about the world, where such plants grow naturally, and devote himself to careful hybridization on the spot. "One might make as much," he writes, "by breeding orchids as by breeding cattle, and of the two, in the long run, I should prefer the orchid farm."
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