Island Life; Or, The Phenomena and Causes of Insular Faunas and Floras

24. M. Sibericus. Also Siberia and China. This is the M. italsi of the Fauna Japonica according to Dr. Gray.

25. Lutronectes whiteleyi. A new genus and species of otter (P. Z. S. 1867, p. 180). In the Fauna Japonica named Lutra vulgaris.

26. Enhydris marina. The sea-otter of California and Kamschatka.

27. Canis hodophylax. According to Dr. Gray allied to Cuon sumatranus of the Malay Islands, and C. alpinus of Siberia, if not identical with one of them (P. Z. S. 1868, p. 500).

28. Vulpes japonica. A peculiar fox. Canis vulpes of Fauna Japonica.

29. Nyctereutes procyonoides. The racoon-dog of N. China and Amoorland.

30. Lepus brachyurus. A peculiar hare.

31. Sciurus lis. A peculiar squirrel.

32. Pteromys leucogenys. The white-cheeked flying squirrel.

33. P. momoga. Perhaps identical with a Cambojan species (P. Z. S. 1861, p. 137).

34. Myoxus japonicus. A peculiar dormouse. M. elegans of the Fauna Japonica; M. javanicus, Schinz (Synopsis Mammalium, ii. p. 530).

35. Mus argenteus. China.

36. Mus molossinus.

37. M. nezumi.

38. M. speciosus.

39. Cervus sika. A peculiar deer allied to C. pseudaxis of Formosa and C. mantchuricus of Northern China.

40. Nemorhedus crispa. A goat-like antelope allied to N. sumatranus of Sumatra, and N. Swinhoei of Formosa.

41. Sus leucomystax. A wild boar allied to S. taeranus of Formosa.

We thus find that no less than twenty-six out of the forty-one Japanese mammals are peculiar, and if we omit the aërial bats (nine in number), as well as the marine sea-otter, we shall have remaining only thirty strictly land mammalia, of which twenty-five are peculiar, or five-sixths of the whole. Nor does this represent all their speciality; for we have a mole differing in its dentition from the European mole; another superficially resembling but quite distinct from an American species; a peculiar genus of otters; and an antelope whose nearest allies are in Formosa and Sumatra. The importance of these facts will be best understood when we have examined the corresponding affinities of the birds of Japan.

Birds.—Owing to the recent researches of some English residents we have probably a fuller knowledge of the birds than of the mammalia; yet the number of true land-birds ascertained to inhabit the islands either as residents or migrants is only 200, which is less than might be expected considering the highly favourable conditions of mild climate, luxuriant vegetation, and abundance of insect-life, and the extreme riches of the adjacent continent,—Mr. Swinhoe's list of the birds of China containing more than 400 land species, after deducting all which are peculiar to the adjacent islands. Only seventeen species, or about one-twelfth of the whole, are now considered to be peculiar to Japan proper; while seventeen more are peculiar to the various outlying small islands constituting the Bonin and Loo Choo groups. Even of these, six or seven are classed by Mr. Seebohm as probably sub-species or slightly modified forms of continental birds, so that ten only are well-marked species, undoubtedly distinct from those of any other country.

The great majority of the birds are decidedly temperate forms identical with those of Northern Asia and Europe; while no less than forty of the species of land-birds are also found in Britain, or are such slight modifications of British species that the difference is only perceptible to a trained ornithologist. The following list of the land-birds common to Britain and Japan is very interesting, when we consider that these countries are separated by the whole extent of the European and Asiatic continents, or by almost exactly one-fourth of the circumference of the globe:—

Land Birds Common to Great Britain and Japan.[146 - Extracted from Messrs. Blakiston and Pryer's Catalogue of Birds of Japan (Ibis, 1878, p. 209), with Mr. Seebohm's additions and corrections in his Birds of the Japanese Empire 1890. Accidental stragglers are not reckoned as British birds.]

(Either Identical Species or Representative sub-species.)

But even these fifty-three species by no means fairly represent the amount of resemblance between Britain and Japan as regards birds; for there are also thrushes, robins, stonechats, wrens, hedge-sparrows, sedge-warblers, jays, starlings, swifts, goatsuckers, and some others, which, though distinct species from our own, have the same general appearance, and give a familiar aspect to the ornithology. There remains, however, a considerable body of Chinese and Siberian species, which link the islands to the neighbouring parts of the continent; and there are also a few which are Malayan or Himalayan rather than Chinese, and thus afford us an interesting problem in distribution.

The seventeen species and sub-species which are altogether peculiar to Japan proper, are for the most part allied to birds of North China and Siberia, but three are decidedly tropical, and one of them—a fruit pigeon (Treron sieboldi)—has no close ally nearer than Burmah and the Himalayas. In the following list the affinities of the species are indicated wherever they have been ascertained:—

List of the Species of Land Birds Peculiar To Japan

1. Accentor rubidus. Nearly allied to our hedge-sparrow, and less closely to the Central Asian A. immaculatus.

(1a. Hypsipetes amaurotis. Migrates to the Corea, otherwise peculiar.)

2. Zosterops japonica. Allied to two Chinese species.

3. Lusciniola pryeri.

4. Garrulus japonicus. Allied to the Siberian and British Jays.

5. Fringilla kawarahiba. Allied to the Chinese greenfinch.

6. Emberiza ciopsis. Allied to the E. Siberian bunting E. cioides, of which it may be considered a sub-species.

7.        ,,      yessoensis. A distinct species.

8.        ,,      personata. A sub-species of E. spodocephala.

9. Gecinus awokera. A distinct species of green woodpecker.

10. Picus namiyei. Allied to a Formosan species.

11. Treron sieboldi. Allied to T. sphenura of the Himalayas, and to a Formosan species.

12. Carpophaga ianthina. A distinct species of fruit-pigeon.

13. Bubo blakistoni. Allied to a Philippine eagle-owl.

14. Scops semitorgues. A distinct species.

15. Phasianus versicolor. A distinct species.

16.        ,,       sœmmeringi. A distinct species.

17.        ,,       scintillaus. A sub-species of the last.

The large number of seventeen peculiar species in the outlying Bonin and Loo Choo Islands is an interesting feature of Japanese ornithology. The comparative remoteness of these islands, their mild sub-tropical climate and luxuriant vegetation, and perhaps the absence of violent storms and their being situated out of the line of continental migration, seem to be the conditions that have favoured the specialisation of modified types adapted to the new environment.

Japan Birds Recurring in Distant Areas.—The most interesting feature in the ornithology of Japan is, undoubtedly, the presence of several species which indicate an alliance with such remote districts as the Himalayas, the Malay Islands, and Europe. Among the peculiar species, the most remarkable of this class are,—the fruit-pigeon of the genus Treron, entirely unknown in China, but reappearing in Formosa and Japan; the Hypsipetes, whose nearest ally is in South China at a distance of nearly 500 miles; and the jay (Garrulus japonicus), whose near ally (G. glandarius) inhabits Europe only, at a distance of 3,700 miles. But even more extraordinary are the following non-peculiar species:—Spizaetus orientalis, a crested eagle, inhabiting the Himalayas, Formosa, and Japan, but unknown in Southern or Eastern China; Ceryle guttata, a spotted kingfisher, almost confined to the Himalayas and Japan, though occurring rarely in Central China; and Halcyon coromanda, a brilliant red kingfisher inhabiting Northern India, the Malay Islands to Celebes, Formosa, and Japan. We have here an excellent illustration of the favourable conditions which islands afford both for species which elsewhere live further south (Halcyon coromanda), and for the preservation in isolated colonies of species which are verging towards extinction; for such we must consider the above-named eagle and kingfisher, both confined to a very limited area on the continent, but surviving in remote islands. Referring to our account of the birth, growth, and death of a species (in Chapter IV.) it can hardly be doubted that the Ceryle guttata formerly ranged from the Himalayas to Japan, and has now almost died out in the intervening area owing to geographical and physical changes, a subject which will be better discussed when we have examined the interesting fauna of the island of Formosa.

The other orders of animals are not yet sufficiently known to enable us to found any accurate conclusions upon them. The main facts of their distribution have already been given in my Geographical Distribution of Animals (Vol I., pp. 227-231), and they sufficiently agree with the birds and mammalia in showing a mixture of temperate and tropical forms with a considerable proportion of peculiar species. Owing to the comparatively easy passage from the northern extremity of Japan through the island of Saghalien to the mainland of Asia, a large number of temperate forms of insects and birds are still able to enter the country, and thus diminish the proportionate number of peculiar species. In the case of mammals this is more difficult; and the large proportion of specific difference in their case is a good indication of the comparatively remote epoch at which Japan was finally separated from the continent. How long ago this separation took place we cannot of course tell, but we may be sure it was much longer than in the case of our own islands, and therefore probably in the earlier portion of the Pliocene period.

Formosa

Among recent continental islands there is probably none that surpasses in interest and instructiveness the Chinese island named by the Portuguese, Formosa, or "The Beautiful." Till quite recently it was a terra incognita to naturalists, and we owe almost all our present knowledge of it to a single man, the late Mr. Robert Swinhoe, who, in his official capacity as one of our consuls in China, visited it several times between 1856 and 1866, besides residing on it for more than a year. During this period he devoted all his spare time and energy to the study of natural history, more especially of the two important groups, birds and mammals; and by employing a large staff of native collectors and hunters, he obtained a very complete knowledge of its fauna. In this case, too, we have the great advantage of a very thorough knowledge of the adjacent parts of the continent, in great part due to Mr. Swinhoe's own exertions during the twenty years of his service in that country. We possess, too, the further advantage of having the whole of the available materials in these two classes collected together by Mr. Swinhoe himself after full examination and comparison of specimens; so that there is probably no part of the world (if we except Europe, North America, and British India) of whose warm-blooded vertebrates we possess fuller or more accurate knowledge than we do of those of the coast districts of China and its islands.[147 - Mr. Swinhoe died in October, 1877, at the early age of forty-two. His writings on natural history are chiefly scattered through the volumes of the Proceedings of the Zoological Society and The Ibis; the whole being summarised in his Catalogue of the Mammals of South China and Formosa (P. Z. S., 1870, p. 615), and his Catalogue of the Birds of China and its Islands (P. Z. S., 1871, p. 337).]

Physical Features of Formosa.—The island of Formosa is nearly half the size of Ireland, being 220 miles long, and from twenty to eighty miles wide. It is traversed down its centre by a fine mountain range, which reaches an altitude of about 8,000 feet in the south and 12,000 feet in the northern half of the island, and whose higher slopes and valleys are everywhere clothed with magnificent forests. It is crossed by the line of the Tropic of Cancer a little south of its centre; and this position, combined with its lofty mountains, gives it an unusual variety of tropical and temperate climates. These circumstances are all highly favourable to the preservation and development of animal life, and from what we already know of its productions, it seems probable that few, if any islands of approximately the same size and equally removed from a continent will be found to equal it in the number and variety of their higher animals. The outline map (at page 392 (#x14_x_14_i48)) shows that Formosa is connected with the mainland by a submerged bank, the hundred-fathom line including it along with Hainan to the south-west and Japan on the north-east; while the line of two-hundred fathoms includes also the Madjico-Sima and Loo-Choo Islands, and may, perhaps, mark out approximately the last great extension of the Asiatic continent, the submergence of which isolated these islands from the mainland.