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Show 378 ISLAND LIFE. (PART JJ. This list exhibits to us the marvellous fact that more than half the peculiar species of Formosan. birds have their n.earest allies in such remote regions as the Himalayas, Sou~h India, the Malay Islands, or Japan, rather than i~ the adJace.nt parts f the Asiatic continent. Fourteen species have Himalayan :Hies, and six of these belong to genera which are unknown in China. One has its nearest ally in the Ni1gherries, and five in the Malay Islands; and of these si~, four belong to ?en~ra which are not Chinese. Two have their only near alhes m J apan. Perhaps more curious still are those cases in which, though the genus is Chinese, the nearest allied species is to be sought for in some remote region. 1 Thus we have the Formosan babbler (Garrulax ruficeps) not al~ied to the sp~cies found in s.outh China, but to one inhabitmg North India and East Thibet; while the black bulbul (Hypsipetes nigerrim1ts), is not alli ed to the Chinese species but to an Assamese form. In the same category as the above we must place eight species not peculiar to Formosa, but which are Indian or Malayan instead of Chinese, so that they offer examples of discontinuous distribution somewhat analogous to what we found to occur in Japan. These are enumerated in the following list. SPECIES OF BIRDS COM:I10N TO F oRMOSA AND INDIA OR MALAYA, BUT NOT FOUND IN CTIINA. 1. Siphia superciliaris. The Rufous-breasted Flycatcher of the S. F, Himalayas. 2. Halcyon coromanda, The Great Red Kingfisher of India, Malaya, an<l . Japan. 3. Palurnbus pulchricollis. The Darjeeling Wood-pigeon of the S. E, Himalayas. 4. Turnix dussumieri. The larger Button-quail of India. 5. Spizaetus nipalensis. The Spotted Hawk-eagle of Nepal and Assam. 6. Lophospiza trivirgata. The Crested Gos-hawk of the Malay Islands. 7. Bulaca newa1·ensis. The Brown Wood-owl of the Himalayas. S: Strix candida. The Grass-owl of India and Malaya. The most interesting of the above are the pigeon and the flycatcher, both of which are, so for as yet known, strictly confined to the Himalayan mountains and Formosa. They thus afford example3 of discontinuous specific distribution exactly CHAP. XVIll.] JAPAN AND FORMOSA. 379 parallel to that of the great spotted kingfisher, a1ready referred to as found only in the Himalayas and Japan. Comparison of the Faunas of 1-Iainan, Formosa, and Japan.The island of Hainan on the extreme south of China, and only separated from the mainland by a strait fifteen miles wide, appears to have considerable similarity to Formosa, inasmuch as it possesses seventeen peculiar land-birds (out of 130 obtained by Mr. Swinhoe), two of which are close allies of Formosan species, while two others are identical. We also find four species whose nearest allies are in the Himalayas. Our knowledge of this island and of the adjacent coast of China is not yet sufficient to enab]e us to form an accurate judgment of its relations, but it seems probable that it was separated from the continent at, approximately, the same epoch as Formosa and Japan, and that the special features of each of these islands is mainly due to their geographical position. Formosa, being more completely isolated than either of the others, possesses a larger proportion of peculiar species of birds, while its tropical situation and lofty mountain ranges has enabled it to preserve an unusual number of Himalayan and :Malayan forms. Japan, almost equally isolated towards the south, and having a much greater variety of c]imate as well as a much larger area, possesses about an equal number of mammalia with Formosa, and an even larger proportion of peculiar species. Its birds, hc;>wever, though more numerous are less peculiar; and this is probably due to the large number of species which micrrate northwards in summer, and find it easy to enter Japan thr~ucrh the Kurile Isles or Saghalien. Japan too, is largely peopled by those northern types which have an unusually wide range, and which, being almost all migratory, are accustomed to cross over seas of moderate extent. The regular or occasional influx of these species prevents the formation of special insular races, such as are almost always produced when a portion of the popu~ ation of a species remains for a considerable time completely Isolated. We thus have explained the curious fact, that while the mammalia of the two islands are almost equally peculiar, (those of Japan being most so in the present state of our. |