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will show that patience and perseverance were not altogether wanting ; but I must plead guilty to having been misled, first by Lesson and then by all the native traders, it never having occurred to me (and I think it could not have occurred to any one), that in scarcely a single instance would the birds be found to inhabit the districts in which they are most frequently to be purchased. Yet such is the case ; for neither at Dorey, nor at Salwatty, nor Waigiou, nor Mysol are any of the rarer species to be found alive. Not only this, but even at Sorong, where the Waigiou chiefs go every year and purchase all kinds of birds of paradise, it has turned out that most of the specimens are brought from the central mountain ranges by the natives, and reach the shore in places where it is not safe for trading praus to go, owing to the want of anchorage on an exposed rocky coast.
Nature seems to have taken every precaution that these, her choicest treasures, may not lose value by being too easily obtained. First, we find an open, harbourless, inhospitable coast, exposed to the full swell of the Pacific Ocean ; next, a rugged and mountainous country, covered with dense forests, offering in its swamps and precipices and serrated ridges an almost impassable barrier to the central regions; and lastly, a race of the most savage and ruthless character, in the very lowest stage of civilization. In such a country and among such a people are found these wonderful productions of nature. In those trackless wilds do they display that exquisite beauty and that marvellous development of plumage, calculated to excite admiration and astonishment among the most civilized and most intellectual races of men. A feather is itself a wonderful and a beautiful thing. A bird clothed with feathers is almost necessarily a beautiful creature. How much, then, must we wonder at and admire the modification of simple feathers into the rigid, polished, wavy ribbons which adorn Paradisea rubra, the mass of airy plumes on P.apoda, the tufts and wires of Seleucides alba, or the golden buds borne upon airy stems that spring from the tail of Cicinnurus regius ; while gems and polished metals can alone compare with the tints that adorn the breast of Parotia sexsetacea and Astrapia nigra, and the immensely developed shoulder-plumes of Epimachus magnus.
My next work was to describe five new birds from New Guinea obtained by my assistant, Mr. Allen, during his last visit there, and also seven new species obtained during his visit to the north of Gilolo and Morty Island. I also described three new species of the beautiful genus Pitta, commonly called ground-thrushes, but more nearly allied to the South American ant-thrushes (Formicariidæ), or perhaps to the Australian lyre-birds. I also began a series of papers dealing with the birds of certain islands or groups of islands for the purpose of elucidating the geographical distribution of animals in the archipelago. The first of these was a list of the birds from the Sula or Xulla Islands, situated between Celebes and the Moluccas, but by their position seeming to belong more to the latter. I believe that not a single species of bird was known from these small islands, and I should probably not have thought them worth visiting had I not been assured by native traders that a very pretty little parrot was found there and nowhere else. I therefore sent Mr. Allen there for two months, and he obtained a small but very interesting collection, consisting of forty-eight species of birds, of which seven were entirely new, including the little parrakeet which I named Loriculus sclateri, and which is one of the most beautiful of the genus. But the most interesting feature of the collection was that it proved indisputably that these islands, though nearer to Bouru and the Batchian group than to Celebes, really formed outlying portions of the latter island, since no less than twenty of the species were found also in Celebes and only ten in the Moluccas, while of the new species five were closely allied to Celebesian types, while only two were nearest to Molluccan species. This very curious and interesting result has led other naturalists to visit these islands as well as all the other small islands which cluster around the strangely formed large island. The result has been that considerable numbers of new species have been discovered, while the intimate connection of these islands with Celebes, so clearly shown by this first small collection, has been powerfully enforced.
During the succeeding five years I continued the study of my collections, writing many papers, of which more than a dozen related to birds, some being of considerable length and involving months of continuous study. But I also wrote several on physical and zoological geography, six on various questions of anthropology, and five or six on special applications of the theory of natural selection. I also began working at my insect collections, on which I wrote four rather elaborate papers. As several of these papers discussed matters of considerable interest and novelty, I will here give a brief summary of the more important of them in the order in which they were written.
The first of these, read in January, 1863, at a meeting of the Zoological Society, was on my birds from Bouru, and was chiefly important as showing that this island was undoubtedly one of the Moluccan group, every bird found there which was not widely distributed being either identical with or closely allied to Moluccan species, while none had special affinities with Celebes. It was clear, then, that this island formed the most westerly outlier of the Moluccan group.
My next paper of importance, read before the same society in the following November, was on the birds of the chain of islands extending from Lombok to the great island of Timor. I gave a list of one hundred and eighty-six species of birds, of which twenty-nine were altogether new; but the special importance of the paper was that it enabled me to mark out precisely the boundary line between the Indian and Australian zoological regions, and to trace the derivation of the rather peculiar fauna of these islands, partly from Australia and partly from the Moluccas, but with a strong recent migration of Javanese species due to the very narrow straits separating most of the islands from each other. The following table will serve to illustrate this :
Species derived from Java ...
This table shows how two streams of immigration have entered these islands, the one from Java diminishing in intensity as it passed on farther and farther to Timor; the other from Australia entering Timor and diminishing still more rapidly towards Lombok. This indicates, as its geological structure shows, that Timor is the older island and that it received immigrants from Australia at a period when, probably, Lombok and Flores had not come into existence or were uninhabitable. This is also indicated by the fact that the Australian immigrants have undergone greater modification than the Javan. If we compare the birds of the whole
chain of islands according as they are of Javan or Australian origin, we have the following results :
We thus see that while the proportion of the birds derived from each source is almost exactly equal, about three-fourths of those from Java have remained unchanged, while threefourths of those from Australia have become so modified as to be very distinct species. This shows us how the distribution of birds can, when carefully studied, give us information as to the past history of the earth.
We can also feel confident that Timor has not been actually connected with Australia, because it has none of the peculiar Australian mammalia, and also because many of the commonest and most widespread groups of Australian birds are entirely wanting. And we are equally certain that Lombok and the islands further east have never been united to Bali and Java, because four Australian or papuan genera of parrots and cockatoos are found in them, but not in Java, as are several species of honeysuckers (Meliphagidæ), a family of birds confined to the Australian region. On the other hand, a large number of genera which extend over the whole of the true Malay islands, from Sumatra to Java, never pass the narrow straits into Lombok. Among these are the long-tail parrakeets (Palæornis), the barbets (Megalæmida), the weaver-birds (Ploceus), the ground starlings (Sturnopastor), several genera of woodpeckers, and an immense number of genera of flycatchers, tits, gapers, bulbuls, and other perching birds which abound everywhere in Borneo and Java.
Two other papers dealt with the parrots and the pigeons of the whole archipelago, and are among the most important of my studies of geographical distribution. That on parrots was written in 1864, and read at a meeting of the Zoological Society in June. Although the Malay Archipelago as a whole is one of the richest countries in varied forms of the parrot tribe, that richness is almost wholly confined to its eastern or Australian portion, for while there are about seventy species between Celebes and the Solomon Islands, there are only five in the three large islands, Java, Borneo, and Sumatra, together with the Malay peninsula, while the Philippine Islands have twelve. This extreme richness of the Moluccas and New Guinea is also characteristic of the Pacific Islands and Australia, so that the Australian region, with its comparatively small area of land, contains nearly as many species of this tribe of birds as the rest of the globe, and considerably more than the vast area of tropical America, the next richest of all the regions.
No two groups of birds can well be more unlike in structure, form, and habits than parrots and pigeons, yet we find that the main features of the distribution of the former, as just described, are found also, though in a less marked degree, in the latter. The Australian region by itself contains threefourths as many pigeons as the whole of the rest of the globe; tropical America, the next richest, having only about half the number; while tropical Africa and Asia are as poor, comparatively, in this group as they are in parrots. Turning now to our special subject, the Malay Archipelago, we find that it contains about one hundred and twenty species of pigeons, of which more than two-thirds (about ninety species) belong to the eastern or Austro-Malayan portion of it, which portion thus contains considerably more species, and much more varied forms and colours, than the whole of South America, Mexico, and the West Indies, forming the next richest area on the globe.
But this is not the only feature in which the parrots and the pigeons resemble each other. Both have characteristic forms and colours, which prevail generally over the whole world. In parrots this may be said to be green, varying into yellow, grey, red, and more rarely blue, and, except for a lengthened tail, having rarely any special developments of plumage. In pigeons, soft ashy lilac or brown tints are