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sufficiently numerous to allow us to determine their relations, and trace their origin, with unusual precision. There are 96 genera and 160 species of land-birds known to inhabit this group of islands; and on a careful analysis, they are found to be almost equally related to the Australian and Oriental regions, 30 genera being distinctly traceable to the former, and the same number to the latter. Their connection with the Moluccas is shown by the presence of the genera Mimeta, Geoffroyus, Cacatua, Ptilopus, and Ianthanas, together with Megapodius and Cerchneis represented by Moluccan species. Turacaena shows a connection with Celebes, and Scops is represented by a Celebesian species. The connection with Australia is shown by the genera Sphaecothera, Gerygone, Myiagra, Pardalotus, Gliciphila, Amadina, and Aprosmictus; while Milvus, Hypotriorchis, Eudynamis, and Eurystomus, are represented by Australian species. Other genera confined to or characteristic of the Australian region, are Rhipidura, Monarcha, Artamus, Campephaga, Pachycephala, Philemon, Ptilotis, and Myzomela.
We now come to the Indo-Malay or Javan element represented by the following genera:
1. Turdus (T.) 11. Oriolus. 21. Yungipicus. 2. Geocichla (T.) 12. Pericrocotus. 22. Merops.
3. Zoothera. 13. Cyornis (T.) 23. Pelargopsis. 4. Megalurus (T.) 14. Hypothymis. 24. Ceyx.
5. Orthotomus. 15. Tchitrea. 25. Loriculus. 6. Pratincola (T.) 16. Lanius (T.) 26. Treron (T.) 7. Oreicola (T.) 17. Anthreptes. 27. Iotreron (s.g. of Ptilopus). 8. Drymocataphus (T,) 18. Eulabes. 28. Chalcophaps (T.) 9. Parus. 19. Estrilda (T.) 29. Gallus (T.) 10. Pycnonotus. 20. Erythrura (T.) 30. Strix.
Such genera as Merops and Stric, which are as much Australian as Oriental, are inserted here because they are represented by Javan species. The list is considerably swelled by genera which have reached Lombok across the narrow strait from Baly, but have passed no further. Such are Zoothera, Orthotomus, Pycnonotus, Pericrocotus and Stric. A much larger number (12) stop short at Flores, leaving only 13, indicated in the list by (T) after their names, which reach Timor. It is evident, therefore, that these islands have been stocked from three chief sources, the Moluccas (with New Guinea and Celebes) Australia, and Java. The Moluccan forms may well have arrived as stragglers from island to island, aided by whatever facilities have been afforded by lands now submerged. Most of the remainder have been derived either from Australia or from Java; and as their relations to these islands are very interesting, they must be discussed with some detail.
Origin of the Timorese Fauna.-We must first note, that 80 species, or exactly one-half of the land-birds of the islands, are peculiar and mostly very distinct, intimating that the immigration commenced long enough back to allow of much specific modification. There is also one peculiar genus of kingfishers, Caridonaw, found only in Lombok and Flores, and more allied to Australian than to Oriental types. The fine white-banded pigeons (s. g. Leucotreron) are also almost peculiar; one other less typical species only being known, a native of N. Celebes. In order to compare the species with regard to their origin, we must first take away those of wide distribution from which no special indications can be obtained. In this case 49 of the landbirds must be deducted, leaving 111 species which afford good materials for comparison. These, when traced to their origin, show that 62 came from some part of the Australian region, 49 from Java or the Oriental region. But if we divide them into two groups, the one containing the species identical with those of the Australian or Oriental regions, the other containing allied or representative species peculiar to the islands, we have the following result:
Species common to the Timorese Islands and the Oriental Region 30 Peculiar Timorese species allied to those of the Oriental Region 19
Total --- --- --- --- --- --- ... 49
Species common to the Timorese Islands and the Australian Region ... --- --- --- --- --- --- ... 18 Peculiar Timorese species allied to those of the Australian Region 44
Total --- --- --- --- --- --- ... 62
This table is very important, as indicating that the connection with Australia was probably earlier than that with Java; since the majority of the Australian species have become modified, while the majority of the Oriental species have remained unchanged. This is due, no doubt, in part to the continued immigration of fresh individuals from Java, after that from Australia, the Moluccas and New Guinea had almost wholly ceased. We must also notice the very small proportion of the genera, either of Australia or Java, that have found their way into these islands, many of the largest and most wide-spread groups in both countries being altogether absent. Taking these facts into consideration, it is pretty clear that there has been no close and longcontinued approximation of these islands to any part of the Australian region; and it is also probable that they were fairly stocked with such Australian groups as they possess before the immigration from Java commenced, or a larger number of characteristic Oriental forms would have been able to have established themselves. On looking at our map, we find that a shallow submerged bank extends from Australia to within about twenty miles of the coast of Timor; and this is probably an indication that the two countries were once only so far apart. This would have allowed the purely Australian types to enter, as they are not numerous; there being about 6 Australian species, and 10 or 12 representatives of Australian species, in Timor. All the rest may have been derived from the Moluccas or New Guinea, being mostly widespread genera of the Australian region; and the extension of Papua in a south-west direction towards Java (which was suggested as a means of providing New Guinea with peculiar IndoMalay types not found in any other part of the region) may have probably served to supply Timor and Flores with the mass of their Austro-Malayan genera across a narrow strait or arm of the sea. Lombok, Baly, and Sumbawa were probably not then in existence, or nothing more than small volcanic cones rising out of the sea, thus leaving a distance of 300 miles between Flores and Java. Subsequently they grew into islands, which offered an easy passage for a number of Indo-Malay genera
north coast of Australia then sank, cutting off the supply from that country; and this left the Timorese group in the position it now occupies.
The reptiles and fishes of this group are too little known to enable us to make any useful comparison.
Insects—The insects, though not numerous, present many fine species, some quite unlike any others in the Archipelago. Such are—Papilio liris, Pieris lacta, Cirrochroa lamarckii and C. leschenaultii among butterflies. The Coleoptera are comparatively little known, but in the insects generally the Indo-Malay element predominates. This may have arisen from the peculiar vegetation and arid climate not being suitable to the Papuan insects. Why Australian forms did not establish themselves we cannot conjecture; but the field appears to have been open to immigrants from Java, the climate and vegetation of which island at its eastern extremity approximates to that of the Timorese group. The insects are, however, so peculiarly modified as to imply a very great antiquity, and this is also indicated by a group of Sylviine birds here classed under Oreicola, but some of which probably form distinct genera. There may, perhaps, have been an earlier and a later approximation to Java, which, with the other changes indicated, would account for most of the facts presented by the fauna of these islands. One deduction is, at all events, clear: the extreme paucity of indigenous mammals along with the absence of so many groups of birds, renders it certain that the Timorese islands did not derive their animal life by means of an actual union with any of the large islands either of the Australian or the Oriental regions.
Celebes Group—We now come to the Island of Celebes, in many respects the most remarkable and interesting in the whole region, or perhaps on the globe, since no other island seems to present so many curious problems for solution. We shall therefore give a somewhat full account of its peculiar fauna, and endeavour to elucidate some of the causes to which its zoological isolation may be attributed.
Mammalia.-The following is the list of the mammalia of Celebes as far as at present known, though many small species may yet be discovered.
1. Cynopithecus nigrescens. 7. Barbirusa alfurus.
The first—a large black ape—is itself an anomaly, since it is not closely allied to any other form of quadrumana. Its flat projecting muzzle, large superciliary crests and maxillary ridges, with the form and appearance of its teeth, separate it altogether from the genus Macacus, as represented in the Indo-Malay islands, and ally it closely to the baboons of Africa.' We have already seen reason to suppose that it has been carried to Batchian, and there is some doubt about the allied species or variety (0. niger) of the Philippines being really indigenous there; in which case this interesting form will remain absolutely confined to Celebes. (2) The tarsier is a truly Malayan species, but it is said to occur in a small island at the northern extremity of Celebes and on some of the Philippine islands. It might possibly have been introduced there. (3) and (4)—a civet and a deer—are, almost certainly, as in the Moluccas, introduced species. (5.) Anoa depressicornis. This is one of the peculiar Celebesian types; a small straighthorned wild-bull, anatomically allied to the buffaloes, and somewhat resembling the bovine antelopes of Africa, but having no near allies in the Oriental region. (6) Sus Celebensis; a peculiar species of wild-pig. (7) Babirusa alfurus; another remarkable type, having no near allies. It differs in its dentition from the typical Suidae, and seems to approach the African Phacochoeridae. The manner in which the canines of the upper jaw are reversed, and grow directly upwards in a spiral curve over the eyes, is unique among mammalia. (8) Five squirrels inhabit Celebes, and all are peculiar species. (9.) These are forest rats of the sub-genus Gymnomys, allied to Australian species. 10. Cuscus. This typical
* The general form of the skull agrees best with that of Cynocephalus mormon, the largest and most typical of the African baboons; while the position of the nostrils brings it nearer the macaques.