nental region, has yet a fauna made up so largely of peculiar types that it seems more in accordance with the facts of distribution to regard it as a separate primary region.

"The Indo-African Realm, as thus restricted, forms a highly natural division. Although its two principal areas are quite widely separated, being in fact geographically almost wholly disassociated, they possess a wonderful degree of similarity. Of the fifty commonly recognized families of mammalia occurring within its limits, three-fifths are distributed throughout almost its whole extent. Of the remainder, one-half are confined to Africa, and one is African and American, leaving only nine in India that are unrepresented in Africa; three only of these latter are, however, peculiar to the Indian Region; all extend beyond it to the northward, five of them even occurring over the greater part of the northern hemisphere. Thus the African region is the more specialized division, only a small portion of the tropical element in the Indian Region, through which it is differentiated from the great Europæo-Asiatic Temper- • ate Region, being unrepresented in the African, while the African has three times as many peculiar families as the Indian."

I am quite unable to appreciate the force of this exposition as an argument in favor of the union of the two regions; it appears to me that it is, indeed, one that tells for the contrary side. Let it be recalled that the ten families* peculiar to the African region are very distinct, and that almost all of the eighteen families "common to both regions" can be added to the twelve "of wide extralimital range," if we take into consideration their distribution in even newer Tertiary or sometimes Quaternary times. Further, the genera even were, for the most part, of wide distribution formerly, and there is strong reason to believe that the thirty forms "common to both regions" were invaders of Africa in the later Tertiary, and that among those now "peculiar to the African region" we have the remnants of older faunæ. If we revert to the fishes we find some striking facts. These can be resolved under two categories. On the one hand a number of forms are peculiar to Africa, or shared in common with South America; on the other are certain genera

There are really more.

shared in common with Asia, or very closely related to Asiatic forms, and well fitted for extension of their range by tenacity of life or adaptation for limited ærial respiration. The evidence here again leads to the conclusion that the peculiar types are derived from very ancient tenants of the territory, while those common to Asia are of recent introduction. We must of course take cognizance of these contrary indications in our appreciation of the relations of the respective regions, and not allow ourselves to be unduly influenced by the predominance of the recent invaders. Africa is a decidedly distinct region so far as its aboriginal population is concerned. Further, its relations, as indicated by its primitive and more characteristic types, are with South America rather than with India, as I shall hereafter show.

THE LEMURIAN OR MALAGASY REALM.

Whether the Malagasy region or Lemurian realm of Allen is independent or an appanage of the African, is the question naturally next in order.

According to Mr. Allen, "As was long since claimed by Dr. Slater, Madagascar is faunally so distinct from every other ontological division of the globe as to be entitled to the rank of a primary zoogeographical region. With it, as is generally admitted, should be associated the Mascarene Islands. The very few mammals indigenous to these islands are decidedly Madagascarine in their affinities, as are the birds and other land animals. While the Lemurian fauna shows decided African affinities, it is second only to the Australian in its degree of specialization. It departs most strikingly from all other regions in what it lacks, through the absence of all Carnivores save one peculiar family (Cryptoproctida), represented by a single species, and four peculiar genera of the family Viverrida; of all Ruminants and Proboscidians; all Pachyderms, except a single African genus of Suidae; and all Rodents, except a few species of Murida. The Insectivores are almost wholly represented by one or two species of Crocidura, and a family, embracing several genera, not found elsewhere, save a single genus in

*Quart. Journ. Sci., vol. i, April, 1864, pp. 213-219 (Allen).

the West Indies. Four families of Bats occur, but are represented, with one exception, by a single species each. They belong to groups of semi-cosmopolitan range, and owing also to the exceptional means of dispersal possessed by the Chiroptera, have little weight in determining the affinities of the fauna. The Quadru

manes are represented only by the Prosimia, of which three-fourths of all the species occur here, while about four-fifths of the remainder are African. The remains of an extinct species of Hippopotamus have been found, a type existing at present only in Africa. Although the Indian genus Viverricula has recently been established as occurring in Madagascar, the few types that connect the Lemurian mammalian fauna with the fauna of other parts of the world are preponderatingly African."

There is much that could be said on both sides of this question, thus ably discussed. When, however, we recall the fact, lately urged, that most of the types that now characterize Africa are comparatively recent immigrants into that continent; that the nearest existing allies of the peculiar mammalian types of Madagascar are to be found among the older types of Africa, and that the few freshwater fishes of Madagascar are of a decided African type, the divergences of the two are materially lessened; there is no dispute that the relations of the Malagasy fauna are most intimate with Africa, and as the question of the distinction of the former from the latter is at least doubtful, and must remain so until its fauna is better known and has been more thoroughly analyzed, we may, provisionally, at least, consider the one as an appanage of the other, having not much less perceptible relations to the main portion than does the Antillean to the South American.

THE SOUTH AMERICAN TEMPERATE REALM.

In Mr. Allen's words, "What is here termed the South American Temperate Realm embraces all that portion of the South American continent and adjacent islands not included in the American Tropical Realm as already defined. It coincides very nearly with Mr. Wallace's South Temperate American or Chilian Sub-region.'*

*Geog. Dist. Animals, vol. ii, p. 36, and map of the Neotropical Region.

Its northern limit on the Atlantic coast is near the thirtieth parallel. On leaving the Atlantic coast, the northern boundary passes obliquely northwestward, rising in the region of the Chaco Desert, to, or possibly a little beyond, the Tropic of Capricorn. Again, descending to about the twenty-fifth parallel, it turns abruptly northward and eastward, along the eastern border of the Andean chain, nearly to the fifth degree of south latitude, near which point it strikes the Pacific coast. It thus embraces a large part of the great Andean plateau, with the neighboring coast region to the westward, nearly all the La Plata plains, and the region thence southward to Tierra del Fuego, which belongs also to this region.

"As contrasted with the Tropical Realm to the northward, it is characterized, in respect to mammals, by the absence of all Quadrumana and the paucity of Edentates and Marsupials, there being neither Sloths nor Anteaters, while only two or three species of Opossums barely extend over its borders; the absence of all genera of Leaf-nosed bats, and of not less than a dozen important genera of Rodents, the Coatis, the Kinkajou, the Tapirs, and many other genera characteristic of the American tropics.* As noted by Mr. Wallace, it is further characterized by the possession of the entire family of the Chinchillida, the genera Auchenia, Habrocomus, Spalacopus, Actodon, Ctenomys, Dolichotis, Myopotamus, Chlamadophorus, to which may be added the marine genera Otaria, Arctocephalus, Morunga, Lobodon, and Stenorhynchus, very few of which range beyond the northern border of this region. The Spectacled Bear is also confined to it, and here are also most largely developed the Murine genera Calomys, Acodon, and Reithrodon."

Mr. Allen might have derived additional cogent evidence for the independence of this realm from the fresh-water fishes, which, in fact, show more relationship to those of New Zealand and Tasmania than to the tropical American types. Indeed, this relationship is such that an English ichthyologist of some note, Dr. Gün

*Among the genera of the Brazilian region here unrepresented are, aside from the Quadrumana, Cercoleptes, Nasua, Tapirus, Bradypus, Chalopus, Myrmecophaga, Tamandua, Cyclothurus, Phyllostoma, Glossophaga, Arctibeus, Dysopes, and other genera of Chiroptera,) Hydrochærus, Cercomys, Dactylomys, Loncheres, Echimys, Calogenys, Dasyprocta, Chatomys, Cercolabes, Lepus, Sciurus, Habrothrix, Oxymycterus, Holochilus, etc., = 27+.”

ther, has considered the several countries as constituents of a single "region," called the Antarctic region, whose subdivisions were designated as the Tasmanian, New Zealand, and Patagonian "subregions," and which were, in his opinion, "almost identical." On the whole I am now inclined to follow Mr. Allen in differentiating this realm from the South American, somewhat contrary to my former views, although I do so with some hesitation.

THE ANTARCTIC OR SOUTH CIRCUMPOLAR REALM.

Mr. Allen has enunciated the following views respecting an Antarctic Realm:

"The Antarctic Realm is geographically almost wholly oceanic, and its fauna hence consists almost exclusively of marine or pelagic species. It necessarily embraces not only the Antarctic Zone, but a large part of the cold south-temperate, since very few of its characteristic species are wholly restricted to the Antarctic waters. It will hence include not only the few small groups of Antarctic Islands, but also Tierra del Fuego and the Falkland Islands, and perhaps also the extreme southern shores of South America, while some of its characteristic forms also extend to New Zealand, and even Australia and the Cape of Good Hope. The only mammals that can be considered as strictly characteristic of this region are Pinnipeds and Cetaceans, of which several genera of each are almost A South Frigid," wholly restricted to it. Antarctic," or "South Circumpolar" "Zone," "Region," or "Realm," has been recognized by various writers for the marine invertebrates, and, by von Pelzeln for birds, with limitations much as here assigned. While the number of species peculiar to it is small, it is large relatively to the whole number represented, especially in the colder latitudes. There is, of course, a broad belt along its northern border of a transitional character, where Antarctic types overlap the range of groups characteristic of south-temperate latitudes."*

66

64

As it is admitted that no terrestrial or fresh-water animals have been found in the Antarctic regions, it is not obvious why such a realm should have been proposed in connection with the distri

*Allen op. cit., p. 372.