Part 9

§ 4. Conclusion.

The affinities or place in nature of the Dodo being thus determined by the characters of its skeleton, but few words remain to be said on the bearings of present knowledge of this species upon other zoological generalizations.

The researches and observations of naturalists have been carried out to such an extent as to support the conclusion that the Didus ineptus does not now live in any part of the world, and that it never existed save in that part of which the island of Mauritius may be a remnant. Consequently the species there originated; and the most intelligible conception of its mode of origin is that to which I have alluded in the description of the brain-case (p. 39).

The Dodo exemplifies Buffon’s idea of the origin of species through departure from a more perfect original type by degeneration; and the known consequences of the disuse of one locomotive organ and extra use of another indicate the nature of the secondary causes that may have operated in the creation of this species of bird, agreeably with Lamarck’s philosophical conception of the influence of such physiological conditions of atrophy and hypertrophy. The young of all Doves are hatched with wings as small as in the Dodo: that species retained the immature character. The main condition making possible the production and continuance of such a species in the island of Mauritius was the absence of any animal that could kill a great bird incapable of flight. The introduction of such a destroyer became fatal to the species which had lost such means of escape. The Mauritian Doves (Columba nitidissima and C. meyeri) that retained their powers of flight continue to exist there.

As I have no reason to offer why one kind of Pigeon should have retained and another lost its powers of flight, nor am able to adduce a particle of evidence of the hypothetical degrees of diminution of the wing-bones to their stunted proportions in Didus, any more than in Dinornis, I feel that in the foregoing remarks I lay myself open to the rebuke of fellow-labourers who may think with the able authors who last treated of the present subject.

They warn their readers to “beware of attributing anything like imperfection to these anomalous organisms, however deficient they may be in those complicated structures which we so much admire in other creatures. Each animal and plant has received its peculiar organization for the purpose, not of exciting the admiration of other beings, but of sustaining its own existence. Its perfection, therefore, consists, not in the number or complication of its organs, but in the adaptation of its whole structure to the external circumstances in which it is destined to live. And, in this point of view, we shall find that every department of the organic creation is equally perfect, the humblest animalcule or the simplest conferva being as completely organized with reference to its appropriate habitat and its destined functions as Man himself, who claims to be lord of all. Such a view of the creation is surely more philosophical than the crude and profane ideas entertained by Buffon and his disciples”.

Nevertheless the truth, as we have or feel it, should be told. In the end it may prove to be the more acceptable service. The Didus ineptus, L., through its degenerate or imperfect structure, howsoever acquired, has perished. What have the stigmatizers of Buffon to offer in lieu of his theory as applied to the origin of this species of bird? They begin by asking, “Why does the whale possess the germs of teeth which are never used for mastication? and why was the Dodo endowed with wings at all, when those wings were useless for locomotion? This question,” they own, “is too wide and too deep to plunge into at present.” They nevertheless proceed to remark, “These apparently anomalous facts are really the indications of laws which the Creator has been pleased to follow in the construction of organized beings; they are inscriptions in an unknown hieroglyphic, which we are quite sure mean something, but of which we have scarcely begun to master the alphabet. There appear, however, reasonable grounds for believing that the Creator has assigned to each class of animals a definite type or structure, from which He has never departed, even in the most exceptional or eccentric modifications of form. Thus, if we suppose, for instance, that the abstract idea of a Mammal implied the presence of teeth, and the idea of a Bird the presence of wings, we may then comprehend why in the Whale and the Dodo these organs are merely suppressed, not wholly annihilated”.

This notion of type-forms or centres, unfortunately, has not merely relation to abstract biological speculations or theories, but to practical questions on which the true progress of Natural History vitally depends. If such types do exist, the National Museum, it is argued, may be restricted to their exhibition: and so our legislators and the public were assured by the Professor of Natural History in the Government School of Mines, when the question was before the “House” four years ago. I have let slip no suitable occasion to combat and expose what has seemed to me to be both an erroneous and mischievous view, most obstructive to the best interests of the science; and, standing alone as I seemed to do on this point in the array of evidence before the “Parliamentary Committee on the British Museum, 1860,” I was glad to find my views on type-forms adopted and paraphrased by the President of the British Association in his Inaugural Address at the Meeting at Nottingham, in the present year.

DESCRIPTION OF THE PLATES.

PLATE I.

Ideal Scene in the island of Mauritius before its discovery, in 1598, by the Dutch, founded on:—

Fig. 1. Picture of the Dodo, by Roelandt Savery, 1626, in the Royal Gallery of Berlin.

Fig. 2. Fac-simile of R. Savery’s Picture of the Dodo, in the possession of the late Wm. J. Broderip, Esq., F.R.S. (no date).

Fig. 3. Picture of the Dodo, by R. Savery, 1628, in the Imperial Collection of the Belvedere, Vienna.

Each figure is coloured, and of the exact size, as in the original paintings.

PLATE II.

Two views of the Dodlet (Didunculus strigirostris, Peale; Gnathodon, Jardine), natural size, from the living bird, obtained at the Samoan or Navigators’ Islands, and transmitted from Sydney, New South Wales, by George Bennett, M.D., F.L.S., to the Gardens of the Zoological Society of London, in 1864, where the paintings, of which the above are fac-similes, were made for the present work. A sketch of the dried head of the Dodo in the Ashmolean Museum, Oxford, of rather less than half the natural size, is introduced into the picture, now in the Author’s possession.

PLATE III.

Fig. 1. Side view of the skeleton of the Dodo (Didus ineptus, L.), with an outline of the bird as represented in the oil-painting presented to the British Museum by Edwards, Naturalist and Librarian of the Royal Society, into whose possession it came at the decease, in 1753, of Sir Hans Sloane, P.R.S., with the statement, or tradition, that the painting had been made, of the natural size, from a living specimen of the Dodo, in Holland. The bones represented in profile, of the natural size, testify to the accuracy of the form and proportions of the Dodo given in the painting.

Fig. 2. An outline of the Samoan Dove or Dodlet (Didunculus strigirostris, Peale; Gnathodon strigirostris, Jardine), of the natural size, from the specimen sent by Dr. G. Bennett, and living, in 1864, in the Gardens of the Zoological Society of London, with a view of the skeleton, corresponding with that of the Dodo.

PLATE IV.

Fig. 1. Front view of the fourth (or first of the three confluent) dorsal vertebræ (centrum and neural arch).

Fig. 2. Vertebral rib, or pleurapophysis, of the same vertebra, front view.

Fig. 3. Sternal rib, or hæmapophysis, of the same vertebra: a, outer side; b, upper or pleural end; c, lower or sternal end; d, front margin; e, inner surface.

Fig. 4. Front view of sternum, or connate mass of hæmal spines, including that of the same (fourth dorsal) vertebra.

Fig. 5. Inner surface of an anterior pleurapophysis, with coalesced appendage, a.

Fig. 6. Oblique view of ditto, ditto.

Fig. 7. Anterior pleurapophysis, with appendage, a, front view: c, capitular end; d, tubercular end; f, hæmal end; 7 a, outer surface; 7 b, inner surface.