CHAP. XII.] THE ORIENTAL REGION. 335 



not superior, in the variety and beanty of its productions, to that 

 which we have just been considering. Like Indo-China, it is a re- 

 gion of forests, but it is more exclusively tropical ; and it is there- 

 fore deficient in many of those curious forms of the temperate 

 zone of the Himalayas, which seem to have been developed from 

 Palsearctic rather than from Oriental types. Here alone, in the 

 Oriental region, are found the most typical equatorial forms of 

 life — organisms adapted to a climate characterised by uniform but 

 not excessive heat, abundant moisture, and no marked departure 

 from the average meteorological state, throughout the year. These 

 favourable conditions of life only occur in three Nvidely separated 

 districts of the globe — the Malay archipelago, Western Africa, 

 and equatorial South America. Hence perhaps it is, that the 

 tapir and the trogons of ]\Ialacca should so closely resemble those 

 of South America ; and that the great anthropoid apes and crested 

 hornbills of Western Africa, should find their nearest allies in 

 Borneo and Sumatra. 



Although the islands which go to form this sub -region 

 are often separated from each other by a considerable ex- 

 panse of sea, yet their productions in general offer no greater 

 differences than those of portions of tlie Indo-Chinese sub- 

 region separated by an equal extent of dry land. The ex- 

 planation is easy, however, when we find that the sea which 

 separates them is a very shallow one, so shallow that an eleva- 

 tion of only 300 feet would unite Sumatra, Java, and Borneo into 

 one great South-eastern prolongation of the Asiatic continent- 

 As we know that our OAvn country has been elevated and de- 

 pressed to a greater amount than this, at least twice in recent 

 geological times, we can have no difficulty in admitting similar 

 changes of level in the Malay archipelago, M'liere the sub- 

 terranean forces which bring about such clmnges are still at 

 work, as manifested by the great chain of active volcanoes in 

 Sumatra and Java. Proofs of somewliat earlier changes of level 

 are to be seen in the Tertiary coal formations of Borneo, which 

 demonstrate a succession of elevations and subsidences, with as 

 much certainty as if we had historical record of them. 



It is not necessary to suppose, nor is it prol)able, that all these 



