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and Australia; and the Australian genera, Adelotopus, Silphomorpha, and Sphallomorpha, form with it a distinct tribe of Coleoptera. These being all confined to the warmer regions, and having so scattered a distribution, are no doubt the relics of a widespread group. The Australian genus, Promecoderus, has, however, closely allied genera (Cascelius and its allies), in Chili and Patagonia; while two small genera confined to the Auckland Islands (Heterodactylus and Pristancyclus) are allied to a group found only in Terra-del-Fuego and the Falkland Islands, (Migadops); and in these cases we may well believe that a direct transmission has taken place by some of the various means already indicated. In Lucanidae, Australia is only moderately rich, having 7 peculiar genera. The most important are Ceratognathus and RhysSonotus, confined to Australia; Lissotes to Australia and New Zealand; Lamprima to Australia and Papua. Mitophyllus and Dendroblaw inhabit New Zealand only; while Syndesus is found in Australia, New Caledonia, and tropical South America. The beautiful Cetoniidae are poorly represented, there being only 3 peculiar genera;-Schizorhina, mainly Australian, but extending to Papua and the Moluccas; Anacamptorhina, confined to New Guinea, and Sternoplus to Celebes. Lomaptera is very characteristic of the Austro-Malay Islands. This almost tropical family shows no approximations between the Australian and Neotropical faunas. In Buprestidae, the Australian region is the richest, possessing no less than 47 genera, of which 20 are peculiar to it. Of these, 15 are peculiar to Australia itself, the most important being Stigmodera (212 species), Ethon (13 species), and Nascio (3 species); Cisseis (17 species), and the magnificent Calodema (3 species), are common to Australia and Austro-Malaya; while Sambus (10 species) and Anthaa!omorpha (4 species), with some smaller groups, are peculiarly Austro-Malayan. In this family occur several points of contact with the Neotropical region. Stigmodera is said to have a species in Chili, while there are undoubtedly several allied genera in Chili and South Temperate America. The genus Curis has 5 Australian and 3 Chilian species, and Acherusia has 2 species in Brazil, 1 in Australia. These resemblances may probably have arisen from intercommunication during the warm southern period, when floating timber would occasionally transmit a few larvae of this family from island to island across the antarctic seas. When the cold period returned, they would spread northward, and become more or less modified under the new physical conditions and organic competition, to which they were subjected. We now come to the very important group of Longicorns, in which the Australian region as a whole, is very rich, possessing 360 genera, of which 263 are peculiar to it. Of these about 50 are confined to the Austro-Malay Islands, 12 to New Zealand, and the remainder to Australia proper with Tasmania. Of the genera confined to, or highly characteristic of Australia, the following are the most important :—Cnemoplites, belonging to the Prionidae; Phoracantha, to the Cerambycidae; Zygocera, Hebecerus, Symphyletes, and Rhytidophora, to the Lamiidae. Confined to the Austro-Malay Islands are Tethionea (Cerambycidae): Tmesisternus, Arrhenotus, Micracantha, and Sybra (Lamiidae); but there are also such Malayan genera as Batocera Gnoma, Praonetha, and Sphenura, which are very abundant in the Austro-Malay sub-region. A species of each of the Australian genera, Zygocera, Syllitus, and Pseudocephalus, is said to occur in Chili, and one of the tropical American genus, Hammatochaerus, in tropical Australia; an amount of resemblance which, as in the case of the Buprestidae, may be imputed to trans-oceanic migration during the Southern warm period. This concludes our illustrations of the distribution of some of the more important groups of Australian insects; and it will be admitted that we have not met with any such an amount of identity with the fauna of Temperate South America, as to require us to modify the conclusions we arrived at from a consideration of the vertebrate groups. r Land-Shells.-The distribution of many of the larger genera of land-shells is very erratic, while others are exceedingly restricted, so that it requires an experienced conchologist to investigate the affinities of the several groups, and thus work out the important facts of distribution. All that can be done here is to note the characteristic and peculiar genera, and any others presenting features of special interest. - In the great family of the snails (Helicidae), the only genera strictly confined to the region are, Partula, now containing above 100 species, and ranging over the Pacific from the Solomon Isles on the west, to the Sandwich Islands and Tahiti on the east; and Achatinella, now containing nearly 300 species, and wholly confined to the Sandwich Islands. Pfeifferia is confined to the Philippine Islands and Moluccas; Cochlostyla to the Indo-Malay Islands and Australia ; Bulimus occurs in most of the insular groups, including New Zealand, but is absent from Australia. Among the Aciculidae, the widely-scattered Truncatella is the only genus represented. Among Diplommatinidae, Diplommatina is the characteristic genus, ranging over the whole region, and found elsewhere as far as India, with one species in Trinidad. The extensive family Cyclostomidae, is not well represented. Seven genera reach the Austro-Malay Islands, one of which, Registoma, is confined to the Philippines, Moluccas, New Caledonia, and the Marshall Islands. Omphalotropis is the most characteristic genus, ranging over the whole region; Callia is confined to the Philippines, Ceram, and Australia; Realia to New Zealand and the Marquesas. The genus Helicina alone represents the Helicinidae, and is found in the whole region except New Zealand. The number of species known from Australia is perhaps about 300; while the Polynesian sub-region, according to Mr. Harper Pease, contains over 600; the AustroMalay Islands will furnish probably 200; and New Zealand about 100; making a total of about 1,200 species for the whole region. . . . AUSTRALIAN SUB-REGIONS.

Few of the great zoological regions comprise four divisions so strongly contrasted as these, or which present so many interesting problems. We have first the Austro-Malay Islands, an equatorial forest-region teeming with varied and beautiful forms of life; next we have Australia itself, an island-continent with its satellite Tasmania, both tropical and temperate, but for the most part arid, yet abounding in peculiar forms in all the classes of animals; then come the Polynesian Islands, another luxuriant region of tropical vegetation, yet excessively poor in most of the higher groups of animals as well as in some of the lower; and lastly, we have New Zealand, a pair of temperate forest-clad islands far in the southern Ocean, with a very limited yet strange and almost wholly peculiar fauna. We have now to consider the general features and internal relations of the faunas of each of these sub-regions, together with any external relations which have not been discussed while treating the region as a whole.

I. Austro-Malayan Sub-region.

The central mass on which almost every part of this subregion is clearly dependent, is the great island of New Guinea, inhabited by the Papuan race of mankind; and this, with the surrounding islands, which are separated from it by shallow seas and possess its most marked Zoological features, are termed Papua. A little further away lie the important groups of the Moluccas on one side and the Eastern Papuan Islands on the other, which possess a fauna mainly derivative from New Guinea, yet wanting many of its distinctive types; and, in the case of the Moluccas possessing many groups which are not Australian, but derived from the adjacent Oriental region. To the south of these we have the Timor group, whose fauna is clearly derivative, from Australia, from Java, and from the Moluccas. Lastly comes Celebes, whose fauna is most complex and puzzling, and, so far as we can judge, not fundamentally derivative from any of the surrounding islands.

Papua, or the New Guinea Group—New Guinea is very deficient in Mammalia as compared with Australia, though this apparent poverty may, in part, depend on our very scanty knowledge. As yet only four of the Australian families of Marsupials are known to inhabit it, with nine genera, several of which are peculiar. It also possesses a peculiar form of wild pig; but as yet no other non-marsupial terrestrial mammal has been

discovered, except a rat, described by Dr. Gray as Uromys VoI. I.-28

aruensis, but about the locality of which there seems some doubt.' Omitting bats, of which our knowledge is very imperfect, the Papuan Mammals are as follows:—

Family. Genus. Species.
Suidae ... ... Sus 1 Eastern limit of the genus.
Muridae ... ... Uromys 1 Aru Islands (?).
Dasyuridae ... Phascogale 1 Australian genus.
, ... Antechinus l 33 35
2? ... Dactylopsila 1 To North Australia only.
29 ... Myoictis 1 Aru islands only.
Peramelidae ... Perameles 1 New Guinea only.
Macropodidae... Dendrolagus 2 New Guinea only.
22 ... Dorcopsis 2 Papua only.
Phalangistidae... Cuscus 7 Celebes to New Guinea.
25 ... Belodeus I Australia and Moluccas.

We have here no sign of any approach to the Mammalian fauna of the Oriental region, for though Sus has appeared, the Muridae (rats and mice) seem to be wanting.

In Birds the case is very different, since we at once meet with important groups, either wholly, or almost peculiar to the Papuan fauna. According to a careful estimate, embodying the recent discoveries of Meyer and D'Albertis, there are 350 species of Papuan land-birds comprised in 136 genera. About 300 of the species are absolutely peculiar to the district, while 39 of the genera are exclusively Papuan or just extend into the Moluccas, or into North Australia where it closely approaches New Guinea. In analysing the genera we may set aside 31 as having a wide range, and being of no significance in distribution; such are most of the birds of prey, with the genera Hirundo, Caprimulgus, Zosterops ; and others widely spread in both the Oriental and Australian regions, as Dicaeum, Munia, Eudynamis, &c. Of the remainder, as above stated, about 39 are peculiar to the Papuan fauna, 50 are characteristic Australian genera; 9 are more especially Malayan, and as much Australian as Oriental; while 7 only, appear to be typically Oriental with a discontinuous distribution, none of them occurring in the Moluccas. .

* See Ann. Nat. Hist., 1873, p. 418, where the species is said to inhabit

the Aru Islands and Celebes, which renders it not improbable that it may have been carried to the former islands from the latter.

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