Page:The Zoologist, 4th series, vol 5 (1901).djvu/137

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recently read before the Royal Society by Mr. W.T. Blanford, LL.D., &c., is written with the object of investigating the zoological divisions of British India and its dependencies, including Ceylon, as shown by the evidence afforded by the eight volumes of the 'Fauna of British India,' containing the descriptions of the Vertebrata. For the purpose of this investigation the whole area of India, Ceylon, and Burma has been divided into tracts, nineteen in number, distinguished by various physical characters, such as rainfall, height above the sea, presence of forest, &c., and tables showing the distribution of each vertebrate genus in these different tracts have been prepared. Briefly the results are the following:—

The whole area contains portions of five different subregions, two of which are assigned to the Holarctic (Palæarctic) region, and three to the Indo-Malay (Indian or Oriental). The first two are (1) the Punjab and Sind, with Baluchistan regarded as appertaining to the Eremian, Tyrrhenian, or Mediterranean province; and (3) the higher Himalayas and Western Tibet, which belong to the Tibetan subregion. The three Indo-Malay subregions are (1) the Cisgangetic, formed by the Indian Peninsula and Ceylon, the only subregion entirely confined to the area; (2) the Transgangetic, comprising the Himalayas, Assam, and Burma within the area, and Southern China, &c., farther to the eastward; and (3) the Malayan, to which Southern Tenasserim is referred. These subregions correspond to those of Wallace, except that his Ceylonese and Indian subregions are united.

The differences between the Cisgangetic and Transgangetic faunas are explained, and it is shown that in Peninsular India, with Ceylon, traces of three distinct elements can be found in the fauna. One of these—the Indo-Malay—is common to India and the countries east of the Bay of Bengal. Another, termed Aryan, is probably a late tertiary, perhaps a pliocene immigrant from Central Asia, and is well represented in the Siwalik fossils; whilst the third, consisting of certain reptiles, batrachians, and invertebrates peculiar to Southern India and Ceylon, is thought to have probably inhabited the country longer than either of the others.

The manner in which the Burmese and Assamese fauna has penetrated the Himalayan forest area, dying out gradually to the westward, is attributed to recent immigation from Assam after the glacial epoch. This and Zool. 4th ser. vol. V., March, 1901.