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worthy of attention. Cuvier from an examination of the internal skeleton of birds, declared that it was, in many instances, impossible to tell the genus, far less than the species. Let us therefore receive with caution such observations, even although they have been considered as plausible by several of the leading geologists.' We examined the casts of those so called foot-marks, in the collection of the Royal College of Surgeons of London, but were not at all convinced of their ornithological origin, and till we have further evidence than such impressions, we would be inclined to argue the contrary; for we are as much, or rather more, entitled to infer that they are only vegetable impressions. To find the remains of birds in such a formation as the new red sandstone would invalidate one of the grand principles of geology.
In tracing out the geographic distribution of the animal and vegetable kingdoms, various methods have been adopted. Some authors, as Humboldt and Latreille, have attempted to trace them according to parallels of longitude and latitude; others, as Illiger, Fischer, &c., according to the various Continents, which no doubt is the most unobjectionable method ; for we find, that when the former is properly examined, it will not stand the test of minute examination, seeing that we have in each of the individual Continents great groups entirely confined, and which have no representatives in any other of the other Continents under similar degrees of longitude and latitude, as we ought to find, if the views of Humboldt, &c. were correct.
Till the laws which regulate the distribution of both the organic and inorganic kingdoms are explained, such a method can never be adopted. We no doubt find secondary causes, such as light, heat, moisture, greater or less distribution of water, configuration of the land, exercising a powerful influence, which is particularly marked out in certain quarters of the globe ; and from authors looking to these individual places alone, they have put more stress upon these causes than what we are entitled to do. Thus, for example, in Northern India, where we find the climate in some places to resemble so much the European, we have a large series of quadrupeds, birds, insects, plants, &c. either identical with the European, or undergoing such slight modifications, as to entitle them to be considered as mere local varieties, or at least the representatives of the European species.
1 Buckland's Bridgewater Treatise.
Akad. d. Wiss. 21. Berlin. 1806, p. 236 et 1812 a. 13, p. 221. 5 Synopsis Animalium et Conspect. Distribut. Geographiæ.
6 Vigors, Zool. Proc. Pt. i. pp. 7, 22, &c. Gould's Cent. of Birds. Wils. Cab. Lib. India, vol. ii. p. 78. Jameson, Wern. Trans. in Ed. New Phil. Jour.
But although these secondary causes seem to have a certain influence in some places, yet that is far from being universal, all appearing to be subject to some great principle hitherto undiscovered, and which will probably remain for ever so.
Nor is it alone in the organic kingdom that we find the distribution liable to vary from unknown causes. In the mineral kingdom we observe phenomena of a similar nature. Thus we find, as has been well remarked, "the geographical distribution of minerals to be very different from mountain rocks; we do not find the same species everywhere, on the contrary, they seem to have many kinds of distribution, in this respect approaching more nearly to what we observe in the physical arrangement of animals and vegetables on the surface of the earth."?
It is foreign to our purpose at present to give all the methods which have been proposed by Humboldt, Latreille, Fabricius, Swainson, &c. in order to point out the erroneous grounds upon which they are based, but shall at present confine our attention to that one most recently given, viz. by Swainson ; and as he has entered into some detail, in regard to the birds of one of his divisions, allowing us an opportunity of refuting his statements, we shall therefore direct particular attention to it; we are the more induced to do so, as no person has ventured to point out the erroneous views of this author, which seem to have been based upon a few and unsatisfactory data.
By Mr. Swainson the globe has been divided into a series of zoological regions or provinces, denominated, ist. the European or Caucasian ; 2d. Asiatic or Mongolian ; 3d. the American ; 4th. the Ethiopian or African ; and, 5th. the Australian or Malay. In the European or Caucasian province lie includes the whole of Europe properly so called, with part of Asia Minor and the shores of the Mediterranean. In Northern Africa, he states, the zoological peculiarities of this region begin to disappear; they are lost to the eastward of the Caucasian mountains, and are blended with those of Asia and America to the north. 2. The Asiatic range comprehends the whole of Asia cast of the Ural mountains, which form a natural and well defined barrier between the two Continents. The chief seat of this zoological region is, he states, probably in Central Asia ; its western confines blend into the European towards Persia, and disappear in the west of the Caucasian chain; it is united to the African range among the provinces of Asia Minor, and is again connected with Europe, and also with America, by the arctic regions of the three Continents ; finally, its
7 Jameson, Werner Trans. Annals of Phil. vol. vi. p. 301.
most southern limits are marked by the islands of Java and Sumatra, where the zoological characters of the Australian regions begin to be apparent. 3. The American province, he states, is uni. ted to Europe and Asia at its northern limits, and comprehends the whole of the New World, but into which it blends at the other extremity is uncertain. 4th. The African province. In it he includes the whole of Africa south of the Great Desert; part, at least, of the countries on the Mediterranean exhibits a decided affinity to the European range ; while the absence of large animals in Madagas. car, and the presence of genera peculiar to New Holland and the extreme point of Southern Africa, lead us to the fifth, or Australian range. 5. Australian province. Australia, New Guinea, and the neighbouring islands, mark its limits in that direction; Australia Proper is its chief seat, and it spreads over the whole of the numerous islands in the Pacific Ocean ; and he moreover remarks, whether this province blends with that of America or Europe, remains for further discovery; but its connexion with Africa and Asia has been already intimated. That the zoology of each of the individual Continents blend with each other at their junction, is a fact that never once has been questioned; but with regard to Madagascar forming the connecting link between Australia and the African Continent, Mr. Swainson can claim no originality in this statement, seeing that it was several years before the publication of Mr. Swainson's elaborate work, pointed out by M. Lesson ;* and it is a remarkable fact that lately several animals considered truly African have been detected in New Holland,' and, on the other hand, several pouched animals, which tribe were supposed to be peculiar to New Holland and America, have been discovered in Madagascar.
The divisions which Mr. Swainson has proposed, appear at first sight very plausible ; but when thoroughly inquired into, will not bear the test of examination. Thus to arrange under one and the same division the Continents of North and South America, Mr. Swainson has taken for granted what nobody has admitted, or can admit, viz. that the geographic distribution of birds is subject to the same laws as those which regulate man." Upon this argument the whole of his divisions seems to be founded, which is quite at variance with all that is yet known in regard to the geographic distribution of animals. In fact, there is no ground whatever for such an argument; nor have we any evidence whatever, on the other hand, to maintain that
8 Annal, de Science Nat. 9 Proceedings of Zool. Soc. of London, 10 The divisions adopted by Mr. Swainson being in accordance with the views of Dr. Pritchard in regard to the distribution of man.
man is liable to be influenced by the same physical laws as those which act upon the lower animals.
If we take into consideration the Continents of North and South America, we shall find them fully as well, if not better, marked out as zoological provinces -at least South America—than any of the others enumerated by Mr. Swainson. Thus among the Mammalia in South America, we find, the genera Priodon, Apara Encoubertes, Dasyprocta Hydrochaerus, Calogenys, " &c. entirely confined ; and in regard to the ornithological kingdom, the genera Pipra, Rupicola, Alector, Craz, Penelope, Dicholophus, Crotophaga, Rhamphastos, Rhea Tanagra, Trochilus, &c. are almost entirely unknown in the Northern Continent. No doubt a few extend their migrations as far north as Mexico; and of the family Trochilide, or Humming-Birds, four are found throughout the Continent of North America; two of these however must be considered as accidental. One, the Trochilus colubris, extends as far north as the 57° or 58° on the west coast," it also frequents the warm plains of Saskatchewan, and Mr. Drummond found its nest near the sources of the Elk river. It advances towards the north as the season lengthens, and delays its visits to the Northern States till the month of May, and still as remarked by Nuttal, as if determined that no flower shall blush unseen, or waste its sweetness on the desert air, it launches at once on wings as rapid as the wind, without hesitation, into the flowery wilderness which borders on the aretic circle." Another species, Trochilus rufus, first discovered by Captain Cook at Nootka Sound, hence denominated the Nootka Sound Humming-Bird, has a much more extensive range, having been found by Kotzebue as far north as the 6lo parallel of latitude on the Pacific coast ; and there are specimens in the Edinburgh Royal Museum of the same species from Mexico. Specimens have also been observed by Swainson from the same quarter, being killed near Real del Monte. In the Trochilus (ornismya) sephanoides, Less. we see a similar distribution in the Southern Continent, it having been discovered by Captain King at the Straits of Magellan, and in honour of whom it has been named the Melisuga Kingii by Vigors," although erroneously, for it does not at all differ from
10 For the different genera of quadrupeds proper to the two continents of America, see Illiger. Loc. Cit. Fischer. Loc. Cit., and Richardson's excellent Report on North American Zool, in Trans of Brit. Asso. vol. v. for those found in North America.
Il Audubon's Amerc. Ornith.
Lesson's species," who is quite correct in giving this name as a synonym. Lesson's specimen was received from Chili, and in the Edinburgh Museum there are several specimens, one of which was received by Professor Jameson from Mexico. The occurrence of Humming-Birds and Parrots in such high southern latitudes was long ago pointed out by Cook. His observations, however, were called in question, and denied by Buffon, but happily found to be quite correct by King." But are four species, two of which are accidental visiters, to be consi. dered equivalent to nearly one hundred which are confined to the Continent of South America ?" The same applies to the Tanagers ; for of the three species found in North America, one alone is proper to it, the other two being also found in South America. The species we allude to, are the Tanagra rubra, Lin. and T. astaca Gm. Numerous other examples could be given from the families Psittacidæ, Falconidæ, Musicapide, Tyrannide, &c. tending to shew the exclu. siveness of the ornithology of South America. Again, when we turn our attention to North America,' we find it characterized by certain tribes, which however are not so numerous as those of the other Continent, but quite sufficient in number to mark it out as provincially distinct from South America. But it is not only by the mam. malogical and ornithological kingdoms that these Continents are so pre-eminently distinguished from each other. In every department of animated nature we find similar characters, to notice any of which is foreign to our subject at present. But although we have divided the Continents of America into but two provinces, yet we believe the time is not far distant when the mammology, ornithology, entomology, &c. shall be better examined, and more attention paid to the individual members of each class ; we shall then instead of two have many zoological provinces. For as in the botanical so in the zoologi. cal kingdom, we shall no doubt find series of birds, quadrupeds, &c.
ving as their fixed places of abode certain regions of the world, beyond which, although a few may migrate, yet upon a careful exa. mination, the greater number will be found to be confined. This statement is well borne out by the collections which frequently reach this country.
Thus what ornithologist who has paid any attention to the subject of the geographic distribution of birds, could not at once distinguish a collection from Southern, from one from Western Africa ; or a collec
15 Man. Ornith. vol. ij. p. 80. Hist. Nat. des Ois. Mouches, p. 69. 16 Zool. Joum. 17 In Mexico a good many species occur. 18 Richardson Loc. Cit. Faun. Bor. Amer. &c.