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Show ) i 350 ISLAND LIFE. (PAR'l' ll. from a continent, yet separated from it by so shallow a sea. Recent changes of sea and land must have occurred here on a, grand scale, and this adds to the interest attaching to the study of this large island. The internal geography of Borneo is somewhat peculiar. A large portion of its surface is lowland, consisting of great alluvial valleys which penetrate far into the interior; while the mountains except in the north, are of no great elevation, and there are no extensive plateaux. A subsidence of 500 feet would allow the sea to fill the great valleys of the Pontianak, Banjarmassing, and Coti rivers, almost to the centre of the island, greatly reducing its extent, and causing it to resemble in form the island of Celebes to the east of it. In geological structure Borneo is thoroughly continental, possessing formations of all ages, with basalt and crystalline rocks, but no recent volcanoes. It possesses vast beds of coal of Tertiary age; and these, no less than the great extent of alluvial deposits in its valleys, indicate great changes of level in recent geological times. Having thus briefly indicated those physical features of Borneo which are necessary for our inquiry, let us turn to the organic world. Neither as regards this great island nor those which surround it, have we the amount of detailed information in a convenient form that is required for a full elucidation of its past history. We have, however, a tolerable acquaintance with the two high er groups-mammalia and birds, both of Borneo and of all the surrounding countries, and to these alone will it be necessary to refer in any detail. The most convenient course, and that which will make the subject easiest for the reader, will be to give, first, a connected sketch of what is known of the zoology of Borneo itself, with the main conclusions to which they point; and then to discuss the mutual relations of some of the adjacent islands, and the series of geographical changes that seem required to explain them. OllAr. XVII.] BORNEO' AND JAVA. 351 ZOOLOGICAL FEATURES OF BORNEO. Mammalia.-About ninety-six species of mammalia have been discovered in Borneo, and of these nearly two-thirds are identical with those of the surrounding countries, and nearly one half with those of the continent. Among these are two Jemurs, three civets, three cats, three deer, the tapir, the elephant, and several squirrels, an assemblage which could certainly only have reached the country by land. The following species of mammalia are supposed to be peculiar to Borneo :- QUADRUMANA. 1. Simia morio. A small orang-utan with large incisor teeth. 2. Hylobates concolo1'. 3. Nasalis larvatu~. 4. Semnopithecus rnbicundns. G. , chrysomelas. G. , frontatus. 7. Macacus melanotus. CARNIVORA. 8. Cynogale bennettii. 9. Paradoxnrns stigmaticus. 10. Herpestcs semitorquatus. l l. , brachyurus. 12. Felis badia. 13. Lutra lovii ( Gunthm·, P. Z. S. 1876, p. 736). UNGULATA. 14. Sus barbatus. RoDEN'riA. 15. Pteromys phreomehu:. 16. Sciurus ephippium. 17. Sciurus pluto. 18. , macrotis. 19. , sarawakensis. 20. , borneonensis. 2l. , rufogularis. ~2. , atrirapillus. 2:3. , rufogaster. 24. AcanthioQ crassispinis. 25. 'l'richys lipnra. • INsEc·rrvonA. 26. Tupaia splendidnla. 27. , minor (Oiinthe1·, P. Z. S. 1876, p. 426). 2'3. Dendrogale murina. 29. Ptilocerus lowii. OmROPTERA. 30. Phyllorina dorire. :31. V esperugo stenopterus. 32. ,, dori re. 33. ,, ty1opus. 34. Taphozous affinis. Of the .thirty-four peculiar species here enumerated, it is probable that when they are more carefully studied some will be found to be identical with those of Malacca or Sumatra; but there are also four peculiar genera which are less likely to be discovered elsewhere. These are Nasalis, the remarkable long-nosed monkey; Cynogale, a semi-aquatic civet; Trichys, a tailless porcupine; and Ptilocerus, a feather-tailed arboreal insectivore. These peculiar forms do not, however, imply that the separation of the island from the continent is of very anr,ient rln.tfl, for the conntry is so vast and so much of the |