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and with the nails of the toes for the most part embedded in the upper surface of the expanded fleshy pads, with which they are terminated, thus affording some resemblance to the abnormal lemuroid mammal Tarsius spectrum of the Indian Archipelago, whence its name is derived. Another peculiarity of the Tarsipes is that its food appears to be exclusively honey, no other substance having been found in the stomachs of the specimens examined, and its long and slender tongue being obviously adapted, like the bill of the humming-bird and the brush-tongue of the lories, for collecting such food.
The Kangaroos (Macropodidæ) must be considered as par esccellence the most important group of the Australian mammal-fauna. They are at once the most numerous in species, and in the former condition of Australia, before the influx of Europeans took place, were probably likewise the most prevalent form of mammalian life as regards individuals. In his great work on the mammals of Australia, Mr. Gould has devoted the whole of the second volume to the illustration of members of this family, figuring no less than forty-four species. Mr. Thomas, in his catalogue of the Marsupialia (12), has recognised fortyfive species.
These are divided into eleven genera, of which the best known and largest are Macropus, Dendrolagus, and Bettongia. The first of these genera contains the larger kangaroos, in which the upper incisors are of equal length, the canine teeth are deciduous when present, and all the toes of the fore feet are of nearly equal length. One of the finest and most brightly coloured of this larger group is the Red Kangaroo (Fig. 5, p. 31), which has been introduced into Europe, and breeds freely in our zoological gardens.
Dendrolagus includes four species of Tree-kangaroos, of which, however, only one is found in Australia, Dendrolagus lumholtzi of Northern Queensland, the others being confined to New Guinea. They are remarkable for the fact
that the proportionate lengths of the fore and hind limbs, unlike those of the true kangaroos, resemble those of ordinary mammals; they further differ from all other kangaroos in being arboreal in their habits, climbing trees with great facility, and living on bark, fruits, and leaves.
Bettongia and its allied genus Potorous embrace the Kangaroo-rats, as they are often termed. These are all small, never exceeding a rabbit in size; they possess welldeveloped canine teeth, and have the central toes of the fore feet elongated to accommodate their digging habits.
Having completed our survey of the Monotremes and Marsupials of the Australian Sub-region, we must now consider the Eutherian series, which, as has been already shown, plays a very subordinate part in this extraordinary fauna. Putting aside the marine mammals—the Seals, Cetaceans, and Sirenians—and confining our attention to the terrestrial groups, we find only three of the usually recognised orders, namely, the Rodents, Bats, and Carnivores, with any representatives in this strange country. And the Carnivores would be perhaps better considered as quite external to the fauna of Australia proper, since the solitary member of this group found within its limits is the semidomesticated Dingo, which, as already suggested, has not improbably been introduced by the primitive native inhabitants.
Monkeys, Insectivores, and the most useful Order of Ungulates, to which its grassy plains would appear to be, and, as we know by actual experience are, excellently adapted, are alike unknown, except as introductions, in Australia, and their functions in a state of nature seem to be performed by the various groups of Marsupials.
Of the other orders, the Rodents are represented by six genera, all belonging to the Mice (Muridx). Of these four are confined to Australia proper, while two others also occur in the Papuan Sub-region; the remaining one, the cosmopolitian Mus, or true Mouse, numbers no less than eighteen species in Australia. The habits of the Watervoles of Europe are assumed by the species of the genus Hydromys, which are modified for aquatic life, while the species of Hapalotis are found chiefly in the dry sandy scrubs.
The Bats, with one exception, all belong to genera of considerably wide distribution, and the number of species known to inhabit Australia is not very great. Thirty only are described in Dr. Dobson's catalogue of the Bats as Australian. Pteropus, the great genus of Fruit-eating Bats, is represented by a few species; so too are the widespread insectivorous genera Vesperugo and Miniopterus. One species of the former genus, the Southern Pipistrelle (V. abramus), is found almost throughout the Old World, from Sweden to North Australia
SECTION V.-ANALYSIS OF THE AUSTRAL
The full list of the Mammalian Fauna of the Austral Sub-region contains the names of about 169 species, referable to fifty-nine genera. Of these genera twenty-nine, just half, are not found outside the Austral Sub-region, the greater number of them (twenty-five) being Marsupials; they include, however, three genera of Mice (Xeromys, Hapalotis, and Mastacomys) and one peculiar Bat (Rhinonycteris). Thirteen genera are confined to the Australian Region, that is, are found in the Papuan Subregion as well as in the Austral Sub-region; of these, again, the majority are Marsupials, besides which there are two genera of Rodents (Hydromys and Uromys), and one Bat (Nyctophilus). Seventeen genera which are found in Australia extend beyond the limits of the Region, to the Oriental, and in some cases range even into the Ethiopian and Palæarctic Regions. Of these the greater number (fourteen) are Bats; one is a Marsupial (Phalanger), of which two species occur in Celebes; another is the widely spread genus Mus, which is found throughout the Old World; and the last is a Carnivore (Canis), of which the Australian representative is the Dingo. Canis is spread over the whole of the rest of the world, both Old and New.
Turning now to the distribution of the genera within the continent of Australia itself, it will be found that out of forty-three genera (of Monotremes, Marsupials, and Rodents), twenty are fairly represented throughout the whole area, thirteen are confined to the east (several of these ranging north into New Guinea), seven are restricted to the western and central parts of the continent (these latter are chiefly desert forms such as Perogale, Choeropus, and Notoryctes), and the three remaining genera are found only in Tasmania. These are Thylacinus, Dasyurus, and Mastacomys.
If now we reconsider the list, counting only Monotremes, Marsupials, and Rodents, it will be found that out of 130 species, thirty-five range from west to east to greater or less extent; forty-nine are confined to the eastern part of Australia, in many cases extending to Tasmania; and thirty-six are peculiar to Western Australia, while ten species out of the whole Mammal-fauna are peculiar to Tasmania.