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of the skin and hair" of cattle. In the English climate an individual Porto Santo rabbit 2 recovered the proper colour of its fur in rather less than four years. The effect of the climate of India on the turkey is considerable. Mr. Blyth describes that bird as being much degenerated in size, "utterly incapable of rising on the wing," of a black colour, and "with long pendulous appendages over the beak enormously developed." Mr. Darwin again tells us that there has suddenly appeared in a bed of common broccoli a peculiar variety, faithfully transmitting its newly acquired and remarkable characters; also that there has been a rapid transformation of American varieties of maize; 5 that certainly "the Ancon and Manchamp breeds of sheep," and that (all but certainly) Niata cattle, turnspit and pug dogs, jumper and frizzled fowls, short-faced tumbler pigeons, hook-billed ducks, &c., and a multitude of vegetable varieties, have suddenly appeared in nearly the same state as we now see them. Lastly, Mr. Darwin tells us, that there has been an occasional development (in five distinct cases) in England of the "japanned" or "black-shouldered peacock" (Pavo nigripennis); a distinct species, according to Dr. Sclater,7 yet arising in Sir J. Trevelyan's flock composed entirely of the common kind, and increasing, "to the extinction of the previously existing breed." Mr. Darwin's only explanation of the phenomenon (on the supposition of the species being distinct) is by reversion, owing to a supposed




1 "Animals and Plants under Domestication," vol. i. 3 Quoted, Ibid. p. 274.

2 Ibid. p. 114.

4 Ibid. p. 324.

5 Ibid. p. 322,

Ibid. vol. ii. p. 414.

7 Proc. Zool. Soc. of London, April 24, 1860.

8 "Animals and Plants under Domestication," vol. i. p. 291.


ancestral cross. But he candidly admits, "I have heard of no other such case in the animal or vegetable kingdom." On the hypothesis of its being only a variety, he observes, "The case is the most remarkable ever recorded of the abrupt appearance of a new form, which so closely resembles a true species that it has deceived one of the most experienced of living ornithologists."

As to plants, M. C. Naudin1 has given the following instances of the sudden origination of apparently permanent forms: "The first case mentioned is that of a poppy, which took on a remarkable variation in its fruit-a crown of secondary capsules being added to the normal central capsule. A field of such poppies was grown, and M. Göppert, with seed from this field, obtained still this monstrous form in great quantity. Deformities of ferns are sometimes sought after by fern-growers. They are now always obtained by taking spores from the abnormal parts of the monstrous fern; from which spores ferns presenting the same peculiarities invariably grow. . . . . The most remarkable case is that observed by Dr. Godron, of Nancy. In 1861 that botanist observed, amongst a sowing of Datura tatula, the fruits of which are very spinous, a single individual of which the capsule was perfectly smooth. The seeds taken from this plant all furnished plants having the character of this individual. The fifth and sixth generations are now growing without exhibiting the least tendency to revert to the spinous form. More remarkable still, when crossed with the normal Datura tatula, hybrids were produced, which, in the

1 Extracted by J. J. Murphy, vol. i. p. 197, from the Quarterly Journal of Science, of October 1867, p. 527.

second generation, reverted to the original types, as true hybrids do." 1

There are, then, abundant instances to prove that considerable modifications may suddenly develop themselves, either due to external conditions or to obscure internal causes in the organisms which exhibit them. Moreover, these modifications, from whatever cause arising, are capable of reproduction-the modified individuals "breeding true."

The question is whether new species have been developed by non-fortuitous variations which are insignificant and minute, or whether such variations have been comparatively sudden and of appreciable size and importance? Either hypothesis will suit the views here maintained equally well (those views being opposed only to fortuitous indefinite variations), but the latter is the more remote from the Darwinian conception, and yet has much to be said in its favour.

Professor Owen considers, with regard to specific origination, that natural history "teaches that the change would be sudden and considerable: it opposes the idea that species are transmitted by minute and slow degrees." 2 "An innate tendency to deviate from parental type, operating through periods of adequate duration," being

1 In confirmation of the suddenness of occasional changes, a remark recently made by Mr. Darwin should be quoted. He says: "It is also well to reflect on such facts as the wonderful growth of galls on plants caused by the poison of an insect, and on the remarkable changes of colour in the plumage of parrots when fed on certain fishes, or inoculated with the poison of toads; for we can thus see that the fluids of the system, if altered for some special purpose, might induce other strange changes." --Descent of Man, vol. i. p. 152.

2 66

Anatomy of Vertebrates," vol. iii. p. 795.

"the most probable nature, or way of operation of the secondary law, whereby species have been derived one from the other." 1

Now, considering the number of instances adduced of sudden modifications in domestic animals, it is somewhat startling to meet with Mr. Darwin's positive assertion that it is " a false belief" that natural species have often originated in the same abrupt manner. The belief may be false, but it is difficult to see how its falsehood can be positively asserted.

It is demonstrated by Mr. Darwin's careful weighings and measurements, that, though little used parts in domestic animals get reduced in weight and somewhat in size, yet that they show no inclination to become truly "rudimentary structures." Accordingly, he asserts,2 that such rudimentary parts are formed "suddenly, by arrest of development" in domesticated animals, but in wild animals slowly. The latter assertion however is a mere assertion; necessary perhaps for the theory of "Natural Selection," but as yet unproved by facts.

But why should not these changes take place suddenly in a state of nature? As Mr. Murphy says: "It may be true that we have no evidence of the origin of wild species in this way. But this is not a case in which negative evidence proves anything. We have never witnessed the origin of a wild species by any process whatever; and if a species were to come suddenly into being in the wild state, as the Ancon Sheep did under domestication, how could you ascertain the fact? If the first of a newly



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Anatomy of Vertebrates," vol. iii. p. 807.

"Animals and Plants under Domestication," vol. ii. p. 318.

3 "Habit and Intelligence," vol. i. p. 344.

begotten species were found, the fact of its discovery would tell nothing about its origin. Naturalists would register it as a very rare species, having been only once met with, but they would have no means of knowing whether it were the first or the last of its race."

To this Mr. Wallace has replied (in his review, in Nature, of Mr. Murphy's work), by objecting that sudden changes could very rarely be useful, because each kind of animal is a nicely balanced and adjusted whole, any one sudden. modification of which would in most cases be hurtful unless accompanied by other simultaneous and harmonious modifications. If, however, it is not unlikely that there is an innate tendency to deviate at certain times, and under certain conditions, it is not more unlikely that that innate tendency should be an harmonious one, calculated to simultaneously adjust the various parts of the organism to their new relations. The objection as to the sudden abortion of rudimentary organs may be similarly met.

Professor Huxley seems now disposed to accept the, at least occasional, intervention of sudden and considerable variations. In his review of Professor Kölliker's criticisms,2 he himself says,3 "We greatly suspect that she" (i.e. Nature) "does make considerable jumps in the way of variation. now and then, and that these saltations give rise to some of the gaps which appear to exist in the series of known. forms."

In addition to the instances brought forward in the second chapter against the minute action of "Natural Selection," may be mentioned such structures as the

1 See Dec. 2, 1869, vol. i. p. 132.


2 Über die Darwin'sche Schöpfungstheorie :" ein Vortrag, von Kölliker; Leipzig, 1864. 3 See "Lay Sermons," p. 342.

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