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in any of the Moluccas, we can hardly suppose that such large animals as the deer and ape, could have reached them by natural means. There is every reason to believe, therefore, that the indigenous Mammalia of the Moluccas are wholly of Papuan stock, and very limited in number.

The birds are much more varied and interesting. About 200 species of land-birds are now known, belonging to 85 genera. Of the species about 15 are Indo-Malayan, 32 Papuan, and about 140 peculiar. Of the genera only two are peculiar-Semioptera, a paradise bird, and Lycocoraz, a singular form of Corvidae; but there is also a peculiar rail-like wader, Habroptila. One genus, Basilornis, is found only in Ceram and Celebes; another, Scythrops, is Australian, and perhaps a migrant. About 30 genera are characteristic Papuan types, and 37 others, of more or less wide range, are found in New Guinea and were therefore probably derived thence. There remains a group of birds which are not found in New Guinea, and are either Palaearctic or Oriental. These are 13 in number as follows:—

1. Monticola. 8. Corydalla.
2. Acrocephalus. 9. Hydrornis.
3. Cisticola. 10. Batrachostomus.
4. Hypolais. 11. Loriculus.
5. Criniger. 12. Treron.
6. Butalis. 13. Neopus.
7. Budytes.

Of these the Monticola, found only in Gilolo, appears to be a straggler or migrant from the Philippine islands. Acrocephalus, of which four species occur, is a wide-spread group; one of the Moluccan birds is an Australian and another a North-Asian species, which perhaps indicates that there has long been some migration southward from island to island, across the Moluccas. Cisticola is a genus of very wide range, extending to Australia. Hypolais is probably a modified form of a Chinese or Javanese species. Criniger is a pure Indo-Malay form, represented here by three fine species. Butalis is a Chinese species, no doubt straggling southward. Budytes and Corydalla are widespread Oriental and Palaearctic species or slight modifications of them. Hydrornis is a Malayan form of Pittidae. Batrachostomus is a distinct representative of a purely Indo-Malay genus. Loriculus is Malayan, and especially Philippine, but it reaches as far as Mysol. Treron is here at its eastern limit, and is represented in Bouru and Ceram by one of the most beautiful species. Neopus, a Malayan eagle, is said to occur in the Moluccas. We find then only three characteristic Indo-Malay types in the Moluccas, Criniger, Batrachostomus, and Treron. All are represented by distinct and well marked species, indicating a somewhat remote period since their ancestors entered the district but all are birds of considerable powers of flight, so that a very iittle extension of the islands in a south-westerly direction would afford the means of transmission, but this could not well have been by way of Celebes, because the two former genera are unknown in that island.

It is evident, therefore, that the Moluccas are wholly Papuan in their zoology; yet they are no less clearly derivative, and must have obtained their original immigrants under conditions that rendered a full representation of the fauna impossible. Such remarkable and dominant types as the eleven genera of Paradiseidae, with Cracticus, Rectes, Todopsis, Machaerirhynchus, Gerygone, Dacelo, Podargus, Cyclopsitta, Microglossum, Nasiterna, Chalcopsitta, and Goura,_all characteristic Papuan groups, found in almost all the islands and most of them very abundant, are yet totally absent from the Moluccas. Taking this, in conjunction with the absence of the two genera of Papuan kangaroos and the other smaller groups of marsupials, and we must be convinced that the Moluccas cannot be mere fragments of the old Papuan land, or they would certainly, in some one or other of their large and fertile islands, have preserved a more complete representation of the parent fauna. Most of the Moluccan birds are very distinct from the allied species of New Guinea; and this would imply that the entrance of the original forms took place at a remote period. The two peculiar genera with clearly Papuan affinities, show the same thing. The cassowary, found only in the large island of Ceram and distinct from any Papuan species, would however seem to have required a land connection for its introduction, almost as much as any of the larger mammalia.

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Taking all the facts into consideration, I would suggest as the most probable explanation, that if the Moluccas ever formed part of the main Papuan land, they were separated at an early date, and subsequently so greatly submerged as to destroy a large proportion of their fauna. They have since risen, and have probably been larger than at present, and rather more closely approximated to the parent land, whence they received a considerable immigration of such animals as were adapted to cross narrow seas. This gave them several Papuan forms, but still left them without a number of the types more especially confined to the forest depths, or powerful enough to combat the gales which often blow weaker flyers out to sea. Most of the birds whose absence from the Moluccas is so conspicuous belong to one or other of these classes. Among the most characteristic birds of the Moluccas are the handsome crimson lories of the genera Lorius and Eos. These are found in every island (but not in Celebes or the Timor group); and a fine species of Eos, peculiar to the small islands of Siau and Sanguir, just north of Celebes, obliges us to place these with the Moluccas instead of with the former island, to which they seem most naturally to belong. The crimson parrots of the genus Eclectus are almost equally characteristic of the Moluccas, and add greatly to the brilliancy of the ornithology of these favoured islands. Reptiles—The Reptiles, so far as known, appear to agree in their distribution with the other vertebrates. In some small collections from Ceram there were no less than six of the genera peculiar to the Australian region, and which were before only known from Australia itself. These are, of snakes, Liasis and Enygrus, genera of Pythonidae; with Diemenia and Acanthophis (Elapidae); of lizards, Cyclodus, a genus of Scincidae; and of Amphibia, a tree-frog of the genus Pelodryas. Insects—Peculiarities of the Moluccan Fauna.-In insects the Moluccas are hardly, if at all, inferior to New Guinea itself. The islands abound in grand Papilios of the largest size and extreme beauty; and it is a very remarkable fact, that when the closelyallied species of the Moluccas and New Guinea are compared, the former are almost always the largest. As examples may be mentioned, Ornithoptera priamus and 0. helena of the Moluccas, both larger than the varieties (or species) of Papua; Papilio ulysses and deiphobus of Amboyna, usually larger than their allies in New Guinea; Hestia idea, the largest species of the genus; Diadema pandarus and Characes euryalus, both larger than any other species of the same genera in the whole archipelago. It is to be noted also, that in the Moluccas, the very largest specimens or races seem always to come from the small island of Amboyna; even those of Ceram, the much larger island to which it is a satellite, being almost always of less dimensions. Among Coleoptera, the Moluccas produce Euchirus longimanus, one of the largest and most remarkable of the Lamellicornes; Sphingnotus dunningi, the largest of the Austro-Malayan Tmesisterninae; a Sphenura, the largest and handsomest of an extensive genus; an unusually large Schizorhina (Cetoniidae); and some of the most remarkable and longest-horned Anthotribidae. Even in birds the same law may be seen at work, in the Tanysiptera nais of Ceram, which has a larger tail than any other in the genus; in Centropus goliath of Gilolo, being the largest and longest-tailed species; in Hydrornis maximus of Gilolo, the largest and perhaps the most elegantly and conspicuously coloured of all the Pittidae; in Platycercus amboinensis, being pre-eminent in its ample blue tail; in the two Moluccan lories and Eos rubra, being more conspicuously red than the allied New Guinea species; and in Megapodius wallacei of Bouru, being the only species of the genus conspicuously marked and banded. All these examples, of larger size, of longer tails or other appendages, and of more conspicuous colouring, are probably indications of a less severe struggle for existence in these islands than in the larger tract of New Guinea, with a more abundant and more varied fauna; and this may apply even to the smaller islands, as compared with the larger in the immediate vicinity. The limited number of forms in the small islands compared with a similar area in the parent land, implies, perhaps, less competition and less danger; and thus allows, where all other conditions are favourable, an unchecked and continuous development in size, form, and colour, until they become positively injurious. This law may not improbably apply to the New Guinea fauna itself, as compared with that of Borneo or any other similar country; and some of its peculiarities (such as its wonderful paradise-birds) may be due to long isolation, and consequent freedom from the influence of any competing forms. The difference between the very sober colours of the Coleoptera, and in a less degree of the birds, of Borneo, as compared with their brilliancy in New Guinea, always struck me most forcibly, and was long without any, even conjectural, explanation. It is not the place here to go further into this most curious and interesting subject. The reader who wishes for additional facts to aid him in forming an opinion, should consult Mr. Darwin's Descent of Man, chapters x. to xv.; and my own Contributions to the Theory of Natural Selection, chapters iii. and iv.

Timor Group—Mammalia.-In the group of islands between Java and Australia, from Lombok to Timor inclusive, we find a set of mammals similar to those of the Moluccas, but some of them different species. A wide-spread species of Cuscus represents the Papuan element. A Sorea, and a peculiar species of wild pig, we may also accept as indigenous. Three others have almost certainly been introduced. These are, (1) Macacus cynomolgus, the very commonest Malay monkey, which may have crossed the narrow straits from island to island between Java and Timor, though it seems much more probable that it was introduced by Malays, who constantly capture and rear the young of this species. (2) Cervus timoriensis, a deer, said to be a distinct species, inhabits Timor, but it is probably only a variety of the Cervus hippelaphus of Java. This animal is, however, much more likely to have crossed the sea than the monkey. (3) Paradocurus fasciatus, takes the place of Viverra tangalunga in the Moluccas, both common and wide-spread civets which are often kept in confinement by the Malays. The Felis megalotis, long supposed to be a native of Timor, has been ascertained by Mr. Elliot to belong to a different country altogether.

Birds.-The birds are much more interesting, since they are

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