There is nothing imperfect in the productions of nature, although there are many organisms in which certain forms and faculties are less developed than in others. There are certainly, in particular groups, such things as rudimentary organs, which belong, as it were, not so much to the individual species, as to the general system which prevails in the larger and more comprehensive class to which such species belong; and in the majority of which these organs fulfil a frequent and obvious function, and so are very properly regarded as indispensable to the wellbeing of such as use them. But there are many examples in animal life which indicate that particular parts of structure remain, in certain species, for ever in an undeveloped state. In respect to teeth, for instance, the Greenland whale may be regarded as a permanent suckling; for that huge creature having no occasion for these organs, they never pierce the gums, although in early life they are distinctly traceable in the dental groove of the jaws. So the Dodo was a kind of permanent nestling, covered with down instead of feathers, and with wings and tail (the oars and rudder of all aërial voyagers) so short and feeble as to be altogether inefficient for the purposes of flight. Why should such things be? We cannot say. Can any one say why they should not be? The question is both wide and deep, and they are most likely to plunge into it who can neither dive nor swim. We agree with Mr Strickland, that these apparently anomalous facts are, in reality, indications of laws which the great Creator has been pleased to form and follow in the construction of organised beings,—inscriptions in an unknown hieroglyphic, which we may rest assured must have a meaning, but of which we have as yet scarcely learned 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."
As to the true position of the Dodo in systematic ornithology, various opinions have been emitted by various men. The majority seem to have placed it in the great Rasorial or Gallinaceous order, as a component part of the family Struthionidæ, or ostrich tribe.
"The bird in question," says Mr Vigors, "from every account which we have of its economy, and from the appearance of its head and foot, is decidedly gallinaceous; and, from the insufficiency of its wings for the purposes of flight, it may with equal certainty be pronounced to be of the Struthious structure. But the foot has a strong hind-toe, and, with the exception of its being more robust, in which character it still adheres to the Struthionidæ, it corresponds to the Linnæan genus Crax, that commences the succeeding family. The bird thus becomes osculant, and forms a strong point of junction between those two contiguous groups."—Linn. Trans. xiv. 484.
M. de Blainville (in Nouv. Ann. du Mus. iv. 24,) contests this opinion by various arguments, which we cannot here report, and concludes that the Dodo is a raptorial bird, allied to the vultures. Mr Broderip, in his article before referred to, sums up the discussion as follows:—
"If the picture in the British Museum, and the cut in Bontius, be faithful representations of a creature then living, to make such a bird of prey—a vulture, in the ordinary acceptation of the term—would be to set all the usual laws of adaptation at defiance. A vulture without wings! How was it to be fed? And not only without wings, but necessarily slow and heavy in progression on its clumsy feet. The Vulturidæ are, as we know, among the most active agents for removing the decomposing animal remains in tropical and inter-tropical climates, and they are provided with a prodigal development of wing, to waft them speedily to the spot tainted by the corrupt incumbrance. But no such powers of wing would be required by a bird appointed to clear away the decaying and decomposing masses of a luxuriant tropical vegetation—a kind of vulture for vegetable impurities, so to speak—and such an office would not be by any means inconsistent with comparative slowness of pedestrian motion."
Professor Owen, doubtless one of our greatest authorities, inclines towards an affinity with the vultures, and considers the Dodo as an extremely modified form of the raptorial order.
"Devoid of the power of flight, it could have had small chance of obtaining food by preying upon the members of its own class; and, if it did not exclusively subsist on dead and decaying organised matter, it most probably restricted its attacks to the class of reptiles, and to the littoral fishes, Crustacea, &c., which its well-developed back-toe and claw would enable it to seize, and hold with a firm gripe."—Transactions of the Zoological Society, iii. p. 331.
We confess that, setting aside various other unconformable features in the structure of the Dodo, the fact, testified by various authorities, of its swallowing stones, and having stones in its gizzard, for the mechanical triturition of its food, (a peculiarity unknown among the raptorial order,) is sufficient to bar the above view, supported though it be by the opinion of our most distinguished living anatomist.
In a recent memoir by Professor J. F. Brandt (of which an abstract is given in the Bulletin de la Class. Phys. de l'Acad. Imp. de St Petersburg, vol. viii. No. 3) we have the following statement:—
"The Dodo, a bird provided with divided toes and cursorial feet, is best classed in the order of the Waders, among which it appears, from its many peculiarities, (most of which, however, are quite referable to forms in this order,) to be an anomalous link connecting several groups,—a link which, for the reasons above given, inclines towards the ostriches, and especially also towards the pigeons."