APPENDIX 



deserves special mention. 1 It is only to be expected that the flora 

 should not be rich in the Bornean secondary forest, and that the plants 

 which form it should belong to the commoner sorts, for being of easier 

 adaptation to the conditions of existence and to the nature of the soil, 

 these are more widely diffused in the neighbouring regions. The secondary 

 forest in Borneo always owes its existence to human agency, which has 

 destroyed the primeval forest ; but in volcanic countries it may be the 

 consequence of an eruption, which may cause the entire vegetation of 

 a mountain to perish. 



In a country where the forests are formed of few species, and the 

 trees are gregarious, the destruction of the primeval vegetation does not 

 produce a great alteration in the flora ; but in a tropical country covered 

 with virgin forests, where hundreds of species of trees, lianas, and epiphytes 

 can be found crowded together in an area of a few square miles, a clear- 

 ance of the forest produces a complete change in the character of the 

 flora, and should such destruction be extended and continued, there can 

 be no doubt that not a few species would be rendered totally extinct. 



It is very probable, indeed almost certain, that in the long run the 

 truly forestal species would regain possession of the secondary forest, 

 once more forming a forest of the primitive type. 



Primeval Forest. — The species of trees which go to form the lofty, 

 primitive forest of Borneo are extraordinarily numerous, and belong to 

 very different families. Those which predominate belong to the Diptero- 

 carpecB, Leguminosce, Elenacece, Sapotacecs, Cupiiliferce, Arctocarpecz , 

 Bombacece, Tiliacece, Dilleniacece, etc. ; but many other trees of moderate 

 dimensions live in the shade of these giants, and contribute to the whole. 

 They belong more especially to the families Myristicacece, Meliacecs and 

 Guttiferce, and principally to the Lauracece and Euphorbiacece . This 

 ' last family, with the exception of a few herbaceous forms, adventitious 

 in inhabited localities, is represented in Borneo entirely by woody 

 species, but few of these are relatively big trees, most of them being 

 shrubs forming the lower growth of the great forest. 



In the primeval forest a large number of the trees and shrubs which 

 live in the shade of the forest giants are naturally young specimens 

 of the latter, but a large proportion of small trees also exist which, even 

 when they attain their full development, never reach the lower branches 

 of the greater trees. Some of these have slender stems, often undivided 

 or but slightly branched, and not many metres high, crowned with scanty 

 but large leaves, simple or pinnate in form. Beneath the shade of the 

 great trees, even those plants which would naturally be herbaceous 

 often become diminutive trees. Even those which are really herbaceous 

 are, without exception, never annuals. 



In some cases the soil of the primeval forest is covered by a thick 



1 The members of this family (herbaceous or woody) are certainly wanting in 

 the primeval forest of Borneo, and only a dozen of adventitious species are found 

 in the vicinity of habitations and cultivated grounds. It thus appears that the 

 damp region of the monsoons is not favourable to the plants with feathery seeds. 

 The Asclepiadece, especially epiphytic species, nevertheless form an exception ; 

 but in these the feathery appendage of the seed is of such a nature that the slightest 

 difference in the hygrometric conditions of the atmosphere render it fit to act as 

 an organ of flight, whilst contact with a wet or even merely damp object causes it 

 at once to adhere. 



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