Abbildungen der Seite

of great birds, alike incapable of flight, and alike with unwebbed feet, differ from each other not merely specifically, but, according to the current value of zoological distinctions, in their wider characters. They are entered, accordingly, in the catalogues under different nomina generica :-Struthio, Rhea, Casuarius, Dromaius. The question of the cause or condition of this insulated and widely-parted location of such nonmigratory birds is one that naturally suggests itself to the inquiring mind, and the enigma becomes more puzzling and more provocative of attempts at solution, when the progress of zoology further discloses the fact, that small islands have, or had recently, their peculiar wingless terrestrial birds, generically distinct from each other, as well as from the larger species of the continents. Thus New Zealand has now its Apteryx, just as, two centuries ago, Rodriguez had its Solitaire, and Mauritius its Dodo, *

The geographical distribution of Quadrupeds seems equally mysterious. The elephant of Africa is specifically distinct from that of Asia; the rhinoceros of the Asiatic continent is onehorned: all the known rhinoceroses of Africa are two-horned. The giraffe and hippopotamus are at present peculiar to Africa, Not any of the indigenous quadrupeds in South America are of the same species with those of the old world--very few are of the same genus. The American monkeys, for example, have four more grinding teeth than those of the corresponding warm latitudes of Africa and Asia : they have the nostrils wider apart, and the tail prehensile in most, to compensate for their incomplete or absent thumbş. The sloths, the armadillos, and the true anteaters are beasts strictly peculiar to South America. Great was the surprise of European naturalists when the discovery of the New World first brought these forms of mammalian life under their notice. Centuries have since elapsed, but the most assiduous researches have failed to make known a species of Bradypus, Dasypus, or true Myrmecophaga, in any other part of the globe. Again, the vast island or continent of Australia has an indigenous quadruped population as peculiar as that of South America, and still more remarkable on account of the general prevalence of the marsupial economy. (It is, we need hardly say, the endowment of the mother with a natural pouch, or tegumentary nest, for the conveyance of her young, which has suggested this name.) With the exception of the native naked

* Bones of this till lately deemed fabulous bird were exhibited by Sir William Jardine, Mr. Strickland, and Professor Milne Edwards, at the late meeting of naturalists at Oxford, where the unique relics of the famous Dodo were duly descanted upon.

biped and his dog, probably a contemporary importation,-not any mammalian species has been discovered in Australia which agrees with a known species or even genus in the rest of the world. New Guinea has its tree-kangaroos, Amboyna and the neighbouring Indian isles their phalangers, and the Americas have their opossums; but the genera Dendrolagus, Cuscus, and Didelphys, to which these extra-Australian marsupials respectively belong, are represented by no species in Australia, which, from the number and variety of other pouched genera, may be called the metropolis of marsupials. Here the true kangaroos (Macropus), the carnivorous opossums (Dasyurus), the wombats (Phascolomys), with a host of other genera, and with the still more extraordinary and anomalous duck-mole (Ornithorhynchus), are features of animal life as distinct from those in the rest of the world, as are the sloths, the ant-eaters, and armadillos of South America, or the giraffe, the hippopotamus, and the orycteropus of Africa. Let any one reflect on the limited powers of locomotion assigned to the last-cited huge fossorial insectivore, to the heavy burrowing wombat, to the climbing sloth, or the diving duckmole, which shuffles awkwardly along dry land like a reptile, and is restricted in the aquatic part of its amphibious existence to tranquil pools of fresh water,-and let him associate these impediments to migration with the facts of the present geographical distribution of the species so fettered; or let him ponder upon the allocation of the few struthious birds which now exist in connexion with their want of wings and of webbed feet:—and say whether Zoology has not presented a problem which, when rightly solved, will effect as great a revolution in men's ideas of the time and the mode of the dispersion of animal life over the earth's surface as the Copernican system did in those regarding the relations of our planet to the sun.

Zoology, by the application of that branch of the science called Palæontology, has already carried us a long way back. With regard to the continents composing what geographers call the old World, it has shown, by its power of determining the natural affinities of extinct species from their fossil remains, that mammalian forms, now limited to particular regions of that great natural tract of dry land, were of yore more generally dispersed over it; that hyænas, elephants, and rhinoceroses, were as common in Europe as they now are in Asia, if not more abundant; and that giraffes and hippopotamuses once co-existed in Africa, Asia, and Europe. The species, indeed, were different; but the same generic forms were at one time widely dispersed over the whole of this Old World, of which they may be regarded as peculiarly characteristic. When, thanks


to the exertions of Sir Woodbine Parish and Mr. Darwin, the extensive tertiary deposits of South America began in their turn to supply analogous evidences of the ancient mammalia of that continent-and when the limestone caverns of Brazil had been ransacked by Lund with a success second only to that which rewarded the previous explorations of Buckland in the same dark recesses of English geology-the results proved so far similar that it could be as truly said of the primeval beasts of America as of those of Europe, that verily there were giants in those days. But the giants appear to have been of totally different orders. No fragment of elephant, rhinoceros, giraffe, , or hippopotamus has been discovered in South America ; but it is inferred from abundant remains of enormous sloths, armadillos, and ant-eaters, and of huge species having near affinities to the lamas (e. g. Macrauchenia), to the cavies (e. g. Tocodon), or to other mammalian families, that such types were at that tertiary epoch, as now, peculiar to this region. Of the dinnensions of some of those extinct representatives of the quadrupeds which may be said to wear the South American livery, an idea


be formed from the fact that certain bones of the megatherium measure exactly double the size of the same bones in the elephant. Forty years ago, difference of size was deemed a matter of such importance in the comparison of species, that Baron Cuvier's just conclusions from his exact demonstrations of the concordance of structure between the megatherium and some of the peculiar existing species of South America, were rejected with the flippant remark that all those species might dance within the carcass of the megatherium.' It might be objected with equal force of the glyptodon, that the present diminutive species of armadillo might all send representatives to disport within its huge panoply, where they would no doubt display more agility there than could be expected from the sloths within the carcass of the megatherium; yet the glyptodon was not less a gigantic armadillo than the megatherium a gigantic sloth. The fact first glimpsed at by Cuvier seems, in a word, to have been abundantly confirmed : viz. that the huge extinct quadrupeds of South America are not allied to those which exhibit similar

proportions in Africa or Asia, but have their nearest affinities to the diminutive species which are now peculiar to South America.

The like correspondence is traced between the recent and the extinct mammals of Australia. Beasts manifesting, in unmistakeable characters stamped upon their fossil remains, the same essential affinities to the kangaroo and wombat, which the megatherium and the glyptodon respectively present to the sloth and armadillo, existed in New Holland contemporaneously with those


edentate giants in South America. Quadrupeds as large as rhinoceroses, and in the proportions of some of their bones approaching the elephant, but representing on a gigantic scale the peculiar features of the existing herbivorous marsupials, subsisted upon the vegetable productions of Australia at the same remote period—judging from the geological character of the strata and the petrified condition of the fossils—at which the mammoth, the rhinoceros, and hippopotamus owned the soil of England-a period anterior to its separation from continental Europe. But more-the vast size of the ancient herbivorous marsupials, and their numbers, as indicated by the abundance of remains discovered in a comparatively brief period, required a system of check; and this was provided for by the co-existence with them of a carnivore bearing to them the same proportional size and force which the ancient lion of England (Felis spelaa) bore to its colossal prey.

But the relics of this Australian carnivore prove it to have been more nearly allied to the small existing carnivorous marsupials of Australia (the dasyures, for example) than to any of the jaguars, lions, tigers, hyænas, or bears of other continents. It was a huge marsupial destructive.

Again-Banks and Solander, throughout Cook's first voyage found no similar tract of land so destitute of mammalian life as the isles of New Zealand; not a trace of the kangaroos and opossums of neighbouring Australia could here be detected. The aborigines, though at that stage of civilization when a knowledge of the beasts of chace is most useful and therefore usually the most exact, could give no information respecting any wild or native quadruped. They had a small half-domesticated dog; but the largest, warm-blooded, indigenous, terrestrial animals hunted or entrapped by them were birds, about the size of our pheasant, but wingless, nocturnal and fossorial; they called them • Kivi.' This condition of New Zealand has been aptly compared by Mr. Lyell with that of Europe during the era of the Wealden formation, in which deposits no traces of animals more highly organized than birds have yet been found.

Thus as large hoofed quadrupeds (the elephant, giraffe, rhinoceros, hippopotamus) form the most striking feature of the zoology of the Old World, as long-clawed edentate quadrupeds do in the case of the New World, or at least of its southern division, and as marsupial quadrupeds prevail in the Australasian world, so wingless birds might be said to form the leading characteristic of the actual zoology of New Zealand. And hence the question became extremely interesting as to what forms of animal life, if any, the deposits contemporaneous with the newer tertiary formations in Australia, South America, and Europe might reveal.


The answer which the explorations of the Rev. Messrs. Williams, Cotton, and Colenso, Colonel Wakefield, and Mr. Earle have enabled Professor Owen to return, is complete. New Zealand was populated at the pleistocene period, by forms of animal life no higher in the scale than wingless birds, and birds most nearly allied to the Kivi (Apteryx) forming the remnant and representative of the family, and now fast disappearing through the exterminating spread of the colonists. But the ancient wingless birds of New Zealand were as gigantic in proportion to the Kivi as the diprotodon of Australia was to the kangaroo. When different species of elephants, rhinoceroses, and hippopotamuses existed in Europe, while as many species of gigantic sloths and armadillos peopled the forests of South America, and when the diprotodons, nototheria, huge wombats, and dasyures represented ihe marsupial order as gigantically in Australia—at the same remote period the dinornis and palapteryx formed a wingless but feathered biped population of the New Zealand isles, comprehending many species, some four feet, some seven feet, some nine feet, some eleven feet in height. Linnæus apostrophized the ostrich as avium maxima! How shrunk are its proportions when viewed by the side of the Dinornis giganteus which towers above the skeleton of the giant O'Byrne in the museum of the College of Surgeons! What adds to the strangeness of this recent discovery and most striking restoration of lost animals, is the fact, that, the number of already ascertained species of struthious or short-winged birds incapable of flight, which once inhabited New Zealand, is nearly three times that of the same order of birds at present known to exist in the rest of the world. Here, therefore, is one of the problems which Zoology offers to the inquiring mind; to explain a generalisation based upon a series of carefully ascertained facts, the conformity, namely, of the geographical distribution of certain groups of the higher organized forms of animal life, at a period antecedent to history, prior apparently to man's existence, with the actual distribution of the same peculiar groups as determined by observation of the living species.

The learned author of the · Researches into the Physical History of Mankind'-in his attempt to reconcile the facts of the geographical distribution of existing animals with certain passages in the Mosaic history as usually interpreted—conjectures that the peculiar extra-Asiatic genera and species might have been called into existence subsequently to the Deluge. The silence of Scripture as to such recent partial creations, Dr. Pritchard holds to be of little consequence.

• It was of no importance,' he says, for men to be informed at what time New Holland began to


« ZurückWeiter »