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I constder, so closely are they related, rather as provinces than regions, and may be termed respectively the Papuan Province and the Australian Province. The former is situated almost wholly between the equator and the twentieth degree of south latitude. The latter embraces that portion of Australia south of this line, together with Tasmania. The boundary between the two regions can of course be drawn only approximately, but may be provisionally assumed as the vicinity of the isotherm of 700 F.* The reason for uniting the northern portion of Australia with New Guinea as a part of the Papuan Province lies in the fact that not only so many of the mammalian genera are common to the two, but that these genera are absent from the more southern portions of Australia, where they are replaced by others wholly restricted to South Australia and Tasmania. Three-fourths of all the genera of Marsupials (excluding, of course, the American family Didelphide) are, so far as at present known, restricted to the Australian Province, as are several genera of Muride and the Ornithorhynchus. Of the remaining Marsupial genera, six only are limited to the Papuan Province.
The Papuan Province.—The Papuan Province embraces not only New Guinea, but the Molucca and Aru Islands on the west and the Solomon
here following sufficiently shows. The principle I still hold as applying to Australia with the same force as elsewhere, only I make the division more to the porthward, as a little more care would have led me to do originally. The York Peninsula, and most probably the whole northern coast region north of 200 S. lat. (except the high arid interior), has certainly closer affinities, as regards mammals, with New Guinea than it bas with any portion of South Australia. Of the strictly Papuan genera, only two out of nine are restricted to New Guinea, the rest being common to both North Australia and Papua. Of the other North Australian genera, about one-balf occur generally throughout the continent, but the remainder are essentially South Australian, represented by only stragglers in Northern Australia. On the other hand, more than twenty genera occurring in Southern Australia and Tasmania, are wholly unrepresented in the portion of Australia I here assign to the Papuan Region. In other words, we get the same wide faunal differences between the tropical and temperate portions of the Australian Realm that we get elsewhere under similar climatic conditions.
In the same connection, Mr. Wallace cites my separation of Temperate South Africa as a primary region as another jostance of the misleading nature of the principle of the distribution of life in zopes. This I have also seen fit to abandon (see anteà, p. 351) on a detailed re-examination of the subject, not because the principle is erroneous, but in consequence of certain peculiar geographical conditions, namely, the comparatively small area subject to a temperate climate and to its limited extension into the temperate region. It is, in fact, wholly within the warm-temperate belt, and widens rapidly northward to abut very broadly against the tropical zone. Only a very small portion really comes under the influence of temperate conditions. Here we get, as usual, a temperate aspect in the fauna, and I still maintain my separation of South Africa as a faunal aivision, simply lowering its grade from a primary region to a “province" of the great IndoAfrican Realm, simply from the fact that the smallness of its area and warm-temperate, rather than temperate, conditions have prevented, as wonld he naturally expected, any great amount of differentiation
* Mr. E. Blyth, in a paper (Nature, vol. iii, p. 428, issue of March 30, 1871) published almost simultaneously with my own cited in the last foot-note, included a portion of Northern Australia in his “Papuan Sub-region", pamely, “York Peninsula and eastern half of Queensland (as far as the dividing range), on the main land of Aust: alia”.
Group on the east, as well as the most northerly portion of Australia, including the York Peninsula, and probably the whole northern coast region, or that portion of Australia north of the Southern Tropic, except the elevated arid interior. Of the twenty-seven genera (exclusive of Chiroptera and marine species) represented in the Papuan Province, ten are not found elsewhere in the Australian Realm. Three of these (Sus, Sorex, found only in the Moluccas, and Mus) have a wide Indo-African range; four (Uromys, Dendrolagus, Dorcopsis, and Myoctis) are found only in New Guinea and the Aru Islands; and one (Dactylospila) in the Aru Islands and the York Peninsula.
The serenteen remaining genera belong more properly to the Australian Province, or perhaps to Australia at large. Many of them, while numerous in species, have here (like Halmaturus, Antechinus, Podabrus, Mus, Hapalotis, etc.) only straggling representatives, but are numerously represented in the temperate region to the southward. The distribution of the genera is approximately indicated in the subjoined table.
Genera of the Papuan Province. NOTE.-The New Guinea representatives of the genera Hapalotis, Phalangista, and Tuchyglossus bave recently been separated from their Australian affines as distinct subgenera. Babirusa is also reported from Bouru, but as probably introduced from Celebes.)
1 New Guinea only.
Aru Islands, New Guinea (Peters), and York'
Peninsula (Krefft). ? Moluccas only.
6 Mainly large South Australian genera, spar; 3 North Australia only.
ingly represented in North Australia and * Also Celebes, Timor, and Moluccas.
New Guinea. *Occurring in New Guinea.
Summary. Total number of genera..... Restricted to the region (including, however, two Indo-African genera) ....... Represented in New Guinea ..... Ranging also over the Australian Region ....... Restricted to New Guinea and neighboring islands (exclusive of two Indo-African
genera)................................. Common to only New Guinea and North Australia ...... Genera properly belonging to the Australian Region, but sparingly represented in
the Papuan Region ........ Distinctively characteristic of the Papuan Region, about...
Australian Province.—The Australian Province, embracing Tasmania and all of Australia south of about the southern isotherm of 700 F.,
contains not less than fifteen to eighteen genera, out of a total number of thirty-four that are restricted to this region, while of the remainder much more than one-half have their chief development here. One-third of the whole are represented in Tasmania, and nearly onefourth range into New Guinea. Two only are peculiar to Tasmania. The distribution of the genera is shown somewhat in detail in the subjoined table.
In this connection it may be added that the close affinity of the Papuan fauna with that of Australia is sufficiently evinced by the fact that of the thirty-four genera represented in South Australia nine range into New Guinea-nearly as many as occur in Tasmania !
Restricted to Tasmania. ?Represented in Tasmania. Mainly restricted to the Papuan Region.
*Occurring in New Guinea.
As was long since claimed by Dr. Sclater,* Madagascar is faunally so distinct from every other ontological division of the globe as to be entitled to the rank of a primary zoögeographical region. With it, as is generally admitted, should be associated the Mascarene Islands. The very few mammals indigenous to these islands are decidedly Ma. dagascarene 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 is what it lacks, through the absence of all Carnivores save one peculiar family (Cryptoproctide),
* Quarterly Journ. Sci., vol. i, April, 1864, pp. 213-219.
represented by a single species, and four peculiar genera of the family Viverridæ; of all Ruminants and Proboscidians; all Pachyderms except a single African genus of Suidæ; and all Rodents except a few species of Muride. 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 the West Indies. Four families of Bats occur, but are represented, with one exception, each by a single species. They belong to groups of semi-cosmopolitan range, and owing also to the exceptional means of dispersal possessed by the Chirnptera, have little weight in determining the affinities of the fauna. The Quadrumanes are represented only by the Prosimiæ, of which three-fourths of all the species occur here, while about four-fitths of the remainder are African. The remains of an extinct species of Hippopotamus bave 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 faunæ of other parts of the world are prepouderatingly African.
With the exception of the Bats, which, for reasons already given, are scarcely entitled to consideration in the present connection, the inammalia of “Lemuria” are, generally speaking, the lowest existing repre. sentatives of their respective orders. The most prominent type, em. bracing, in fact, about three-fifths of all tbe species (excluding the half dozen species of Chiroptera), belong to the Prosimiæ, the lowest of the Quadrumanes, which in early Tertiary times bad representatives over a large part of the northern hemisphere, and perhaps had at that time a pearly cosmopolitan distribution. The Carnivores are likewise allied to early types of the Viverride, which formerly had a much wider range than at present; and the Insectivores are also of low forms, and allied to early types. These facts seem, at first sight, to lend support to the hypothesis, first advanced by Dr. Sclater, that Madagascar and the Mas. carene Islands are but remuants of a former extensive land-area that possibly had connection with America as well as India, and embraced portions of Africa. The supposed former relationship with America is indicated perhaps not so much by the presence of Solenodon in the West Indies, and of American forms of Serpents, Lizards, and Insects in Ma. dagascar, as by the abundant occurrence of Lemuroid remains in the North American Eocene. Since, however, these early Lemuroid forins appear not to bave been true Lemurs, but a more generalized type, having affinities also with the Carnivores and Insectivores, and since they occur. red also in Europe, and probably in Asia (for recent palæontological discoveries in our American Tertiaries show that much may be expected from future explorations elsewhere), it is possible tbat the explanation of the present distribution of the Prosimic needs not the supposition of the existence of any very extensive land-area that has since disappeared: in other words, that the African and Madagascarene Lemuridæ may
have reached their present homes by migration from the northward (leaving a remnant in India), at a time when North America and Asia formed a continuous land-area, just as there is good reason for believing that the greater part of the present faunæ of India, Southern Europe, and Africa are a comparatively recent immigration from the northward; that Madagascar derived, at a comparatively early period, its existing fauna from Africa, as Mr. Wallace believes to have been the fact; and, finally, that at a time antedating the appearance of the present African fauna, Madagascar was actually united to the African continent.* America is now not only currently considered to be the “Old World” geologically, but it seems probable, as has recently been suggested,t that the Equine, Tapiroid, Rhinoceroid, Cameloid, Suilline, and Cervine forms, the Prosimiæ, and possibly the Proboscidians, Marsupials, and Eden tates, were either first developed in America, or bad their origin there in early generalized forms, and have since spread to the more recently formed continents of the eastern hemisphere. Many of them, as well as other early, generalized types, are known to have had a pearly contemporaneons existence during the early part of the Tertiary period both in America and Europe. This certainly lends probability to Mr. Wallace's hypothesis respecting the origin of the present Lemurian fauna.
The families and genera represented in 6 Lemuria", their faunal alli. ances, and areas of chief distribution, are as follows: LEMURIDÆ.—Chiefly developed in Madagascar, but occurring in Tropical Africa, South
ern India, and the Malay Archipelago. Represented by about twelve genera and about fifty species, three-fifths of which are peculiar to Madagascar, and three-fourths of the remainder to Africa. Genera :—Indris,
Propithecus, Lemur, Hapalemur, Microcebus, Lepilemur, Chirogaleus. DAUBENTONIIDÆ.—Peculiar to Madagascar and represented by a single species-Dau
bentonia (=Chiromys) madagascariensis. CRYPTOPROCTIDÆ.—One species (Cryptoprocta ferox), found only in Madagascar. VIVERRIDÆ.-Warmer parts of Asia, the Malayan Islands, and Africa. Represented
in Madagascar by several peculiar genera and the Indian genus Viverricula. Gepera :-Fossa, Galidia, Galidictis, Viverricula. Species of the African
genus Herpestes also reported.
African genus Potamochærus.
believed to have but recently become extinct.
Madagascar and the Mascarene Islands by two species of the Indian and
Australian genus Pteropus.
by species of Rhinolophus.
* Geogr. Distr. Anim., vol. i, p. 273; Nature, vol. xvi (Oct. 25, 1877), p. 548. .
* See especially Prof. 0. C. Marsh's address on “the Introduction and Succession of Vertebrate Life in America”, delivered before the Nashville meeting of the American Association for the Advancement of Science, Aug. 30, 1877.