the more concentratively simplified and specialised foot of the Horse.'

Rhinoceroses and Zebras, however, tread together the arid plains of Africa in the present day: and the Horse has multiplied in that half of America where two or more kinds of Tapir still exist. That the continents of the eocene or miocene periods were less diversified in respect of swamp and sward, pampas or desert, than those of the pliocene period, has no support from observation or analogy.

Assuming, then, that Palæotherium did ultimately become Equus, I gain no conception of the operation of the effective force by personifying as Nature' the aggregate of beings which compose the universe, or the laws which govern these beings, by giving to my personification an attribute which can properly be predicated only of intelligence, and by saying, 'Nature has selected the mid-hoof and rejected the others.'

As some paragraphs in my Preface' have been misconceived,2 I must further observe, to put my meaning beyond doubt, that, to say that Palæotherium has graduated into Equus by Natural Selection' is an explanation of the process of the same kind and value as that which has been proffered of the mystery of secretion.' For example, a particular mass of matter in a living animal takes certain elements out of the blood and rejects them asbile.' Attributes were given to the liver which can only be predicated of the whole animal: the appetency' of the liver, it was said, was for the elements of bile, and 'biliosity' or the hepatic sensation' guided the gland to their selection.3

Such figurative language, I need not say, explains absolutely nothing of the nature of bilification. One's surprise is that tropes' and 'personified acts' should not have died out, as explanatory devices, with the archeus faber,' the 'nisus formativus,' and other self-deceiving, world-beguiling simulacra of science, with the last century; and that a resuscitation should have had any success in the present. It is of interest as illustrating the 'alternation of generations.'

What, then, are the facts on which any reasonable or intelligible conception may be formed of the mode of operation of the

1 XVII. p. 397.

2 Referring to my Anatomy of Vertebrates,' in the fourth edition of the ‘Origin of Species by Natural Selection,' &c., the author asserts that 'he' (Professor Owen) at the same time admits that Natural Selection may have done something towards this end.' Mr. Darwin does not quote the passage or refer to the page on which he founds his assertion.-ccxIII" (1866), Histor. Pref. p. xviii.

3 CCCXXVIII". vol. i. p. 268, and passim.

derivative law exemplified in the series linking on Palæotherium to Equus? A very significant one is the following:-A modern horse occasionally comes into the world with the supplementary ancestral hoofs. From Valerius Maximus,' who attributes the variety to Bucephalus, downwards, such polydactyle' horses have been noted as monsters and marvels. In one of the latest examples, the inner splint-bone, answering to the second metacarpal of the pentadactyle foot, supported phalanges and a terminal hoof, in position and proportion to the middle hoof, resembling the corresponding one in Hipparion, fig. 614, II.

In relation to actual horses such specimens figure as 'monstra per excessum;' but, in relation to miocene horses, they would be normal, and those of the present day would exemplify 'monstra per defectum.' The mother of a 'monstrous' tridactyle colt might repeat the anomaly and bring forth a tridactyle filly'; just as, at San Salvador, the parents of a family of six had two of the series born with defective brain and of dwarf size: they were male' and 'female;' and these strange little idiots are exhibited as 'Aztecs.' The pairing of the horses with the metapodials bearing, according to type, phalanges and hoofs, might restore the race of hipparions.

Now, the fact suggesting such possibility teaches that the change would be sudden and considerable: it opposes the idea that species are transmuted by minute and slow degrees. It also shows that a species might originate independently of the operation of any external influence; that change of structure would precede that of use and habit; that appetency, impulse, ambient medium, fortuitous fitness of surrounding circumstances, or a personified selecting Nature,' would have had no share in the transmutative act.

There is, however, one relation which I cannot shut out, for I hold it as strongly as when I explained it, and endeavoured to impress it upon the audience at my lectures of 1857 it is the fitness of the organisation of the Horse and Ass for the needs of

14 Exemplorum memorabilium Libri novem, &c. (De rebus mirificis.)' ccciv". p. 55, Pl. 1.

Two such examples are described in LII. vol. ii., and one in cccv". p. 224, in which the left fore-foot had three subequal hoofs, and the right fore-foot two hoofs. But the application of an instructive and rightly discerned relation may be travestied and exaggerated the two-tailed lizard and the double-headed snake do not reproduce to view normal ancestral forms. The essentially single mid-toe (fig. 193, iii) of the horse, occasionally bifid and terminated by a pair of ill-shapen hoofs, lends no support to the idea of the digit (iii) being homologous with the so-called cloven hoof (really the digits iii and iv, ib.) of Ruminants. It is a malformation akin to that of the partially double digit of the Dorking fowl.

mankind, and the coincidence of the origin of Ungulates having equine modifications of the perissodactyle structure with the period immediately preceding, or coincident with, the earliest evidence of the Human Race.

Of all the quadrupedal servants of Man none have proved of more value to him, in peace or war, than the horse: none have cooperated with the advanced races more influentially in Man's destined mastery over the earth and its lower denizens. In all the modifications of the old palæotherian type to this end, the horse has acquired nobler proportions and higher faculties, more strength, more speed, with amenability to bit. No one can enter the saddling ground' at Epsom, before the start for the 'Derby,' without feeling that the glossy-coated, proudly-stepping creatures led out before him are the most perfect and beautiful of quadrupeds. As such, I believe the Horse to have been predestined and prepared for Man. It may be weakness; but, if so, it is a glorious one, to discern, however dimly, across our finite prisonwall, evidence of the Divinity that shapes our ends,' abuse the

means as we may.

6

Thus, at the acquisition of facts adequate to test the moot question of links between past and present species, as at the close of that other series of researches proving the skeleton of all Vertebrates, and even of Man, to be the harmonised sum of a series of essentially similar segments,' I have been led to recognise species as exemplifying the continuous operation of natural law, or secondary cause; and that, not only successively but progressively; from the first embodiment of the Vertebrate idea under its old Ichthyic vestment until it became arrayed in the glorious garb of the Human form.’2

6

The series of observations on the Ungulate group of Mammals yields insight, as above explained, into the mode of operation of the secondary law; and gives evidence of the amount of geological time intervening between the introduction and disappearance of generic or subgeneric modifications. According to

1 CXLI. p. 119. 2 Ib. p. 86. Even in his partial quotation from my work of 1849, the author of CCXIII" (4th Ed. 1866) might have seen ground for apologising for his preposterous assertion, in 1859:-that 'Professor Owen maintained, often vehemently, the immutability of species' (p. 310), and for the question, as preposterous and unworthy: 'Does he really believe that at innumerable periods in the earth's history elemental atoms have been commanded suddenly to flash into living tissues?' (Ib. Ed. 1859, p. 483. In the Ed. of 1860, p. 111, the imputation is tacitly abandoned.) The significance of the concluding paragraphs of CXLI was plain enough to BADEN POWELL, cccxxx". p. 401 (1855), and drew down on me the hard epithets with which Theology usually assails the inbringer of unwelcome light, ci'. p. 61.

the analogy of the mammalian Hipparion and Equus, we may expect the corresponding precedent form of the Papuan of the well-wooded and richly fruited islands representing a departed tropical or subtropical continent, to be exemplified by fossils in formations not earlier than middle tertiary. All species coexisting with the actual specific form of Homo will, with him, be immutable, or mutable only as he may be. To name such species, after comparing and determining their specific characters, will continue to be the Zoologist's staple task as long as his own specific intellectual character remains unchanged (Pref. p. xxxvi.). To suppose that coexisting differentiations and specialisations, such as Equus and Rhinoceros, or either of these and Tapirus, which have diverged to generic distinctions from an antecedent common form, to be transmutable one into another, would be as unscientific, not to say absurd, as the idea, which has been bolstered up by so many questionable illustrations, and foisted upon poor working men,' of their derivation from a Gorilla!

§ 425. Extinction, cataclysmal or regulated?—If, in place of recognising the series of the above-cited Perissodactyles as evidencing (preordained) departures from parental type, probably sudden and seemingly monstrous, but adapting the progeny inheriting such modifications to higher purposes, the theological notion be retained, and the species of Palæothere, Paloplothere, Anchithere, Hipparion, and Horse, be severally deemed due to remotely and successively repeated acts of direct creation, one is concomitantly led to suppose the successive going out of such species to have been as miraculous as their coming in. The destruction of one creation is the logical preordinance to a recurrence of 'genesis.' This nexus of ideas was too close not to have swayed with Cuvier: accordingly, in his famous Discours sur les Révolutions de la Surface du Globe,' we have a section of Preuves que ces Révolutions ont été nombreuses," and another section of Preuves que ces Révolutions ont été subites.' 2 Continued observations of Geologists, while establishing the fact of successive changes, have filled up the seeming chasms between such supposed revolutions,' as the discoveries of Palæontologists have supplied the links between the species held to have perished by the cataclysms. Each successive parcel of geological truth has tended to dissipate the belief in the unusually sudden and violent nature of the changes recognisable in the earth's surface. In specially directing my attention to this moot point, whilst engaged in investigations of fossil remains, and in 2 Ib. p. 8.

1 cccxx". p. 5.

the reconstruction of the species to which they belonged, I was, at length, led to recognise one cause of extinction as being due to defeat in the contest which as a living organised whole, the individual of each species had to maintain against the surrounding agencies which might militate against its existence.' (Pref. p. xxxiv.) This principle has received a large and most instructive accession of illustrations from the extensive knowledge and devoted labours of Charles Darwin: but he aims to apply it not only to the extinction but the origin of species.

Although I fail to recognise proof of the latter bearing of the 'battle of life,' the concurrence of so much evidence in favour of 'extinction by law' is, in like measure, corroborative of the truth of the ascription of the origin of species to a secondary cause.1

A critic of the first volume of the present work, switching over the pages of the 'Preface' with the speed they merited at his hands, caught sight of the words, 'contest of existence,' battle of life;' and thereupon dashed off with- We would call attention to the following passage, and ask whether it is not actually an admission of the Darwinian Theory!' (London Review,' April 28, 1866, p. 483); then pastes in the slip, beginning with 'the actual presence,' to 'fared better in the battle of life.' With the bulk of the two volumes before him, an able reviewer could hardly be expected to waste valuable time upon 'notes,' and so the fact escaped him that the admission' or 'adoption' was, in whatever degree it might relate to the D. T., an anticipation.

Oddly enough, another reviewer (if haply the same meritorious labourer may not have been doing this sort of work for both periodicals) makes the same transposition of dates, mistaking a quotation for text; e.g. 'Not the least important feature in the work before us is, that it contains a partial concurrence, on the part of the author, in the theory of Natural Selection. And the same cutting does duty as 'pièce justificative,' viz., 'The actual presence,' &c. to battle of life.'-('Popular Science Review,' April, 1866, p. 212.)

Having regard to intelligent countrymen and countrywomen taking scientific sustenance from these weekly and monthly sources, and who might never see the pages of the work reviewed, I ventured to call attention to the omitted reference in the foot-note of my 'Preface,' viz., to the volume of 'Transactions of the Zoological Society,' 1850, in which my theory of the extinction and conservation of species appeared, including the passage quoted, with the obvious remark, that, 'if the difference between 1858 (date of the D. T. or "Natural Selection") and 1866 (date of vol. i. of Anat. of Vertebrates) puts the writer of the latter date in the subordinate relation of "admitter" or "adopter"-tacit or otherwise-to the author of the same theory at the earlier date, the writer of 1858 must stand in the same relation to the author of the same theory of 1850.'-(Letter to ED. ct 'London Review, May 1st, 1866.)

Of course, to every competent judge, the difference between a theory founded on the application of the principle of the contest for existence to the preservation or extinction of certain species, and that of a theory of the origin of all species partially based upon the same principle, must have been obvious; nor was any pretention advanced, in the letter rectifying the date of the 'idea,' to the ample and instructive degree in which it had been worked out, and doubtless as an original thought, by the accomplished author of ccxin".

I deeply regretted, therefore, to see in a 'Historical Sketch' of the Progress of Enquiry into the origin of species, prefixed to the fourth edition of that work (1866), that Mr. Darwin, after affirming, inaccurately and without evidence, that I admitted