APPENDIX . 



described, and in which the growth of vegetation is continuous and active 

 throughout each day of the year, must necessarily be clothed with a 

 high, dense, and luxuriant arboreal mantle, with evergreen foliage, from 

 the seashore to the summits of its mountains. And this, indeed, is 

 the marked feature which I would call the " physical characteristic" of 

 the flora of Borneo. There being no season during which the vegetative 

 functions are quiescent, either on account of a low temperature or by 

 reason of a prolonged drought, it is easy to see why in Borneo neither 

 annual (forestal) plants, nor terrestrial bulbous plants, nor thickened 

 tree-trunks, nor fleshy ground-plants are to be found. 



A sort of correspondence to the above-mentioned physical forms 

 of plants is to be met with in the world of Epiphytes, where, on the naked 

 trunk and branches of the trees, alternate periods of dampness and 

 dryness occur, corresponding with the climatic periods. Similarly 

 amongst the epiphytes in Borneo, on the better lighted and higher parts 

 of trees, we meet with plants termed " Xerophiles " or lovers of dryness, 

 which are so organised as to be able to exist for a longer or shorter period 

 without water, but which are at the same time provided with special 

 adaptations enabling them to take advantage of it when it does occur 

 on . any occasion and under any physical condition. 



The soil which nourishes the forest trees of Borneo, especially in the 

 plains, is always loaded with moisture, and at the same time is never 

 too much heated, being sheltered by the dense foliage of the trees them- 

 selves. For this reason the greater portion of the tropical sylvan plants, 

 living on the sea level, only flourish under a moderate temperature, say 

 from 70 to 90 Fahr. _When I use the term forest, I refer only to that 

 which is really primeval, which in Borneo is characterised by the great 

 size of the arboreal vegetation, by the infinite variety of species which 

 form it, and by the great number of peculiar forms. In Borneo, except 

 along the coasts where mangroves and casuarinas are found, woods entirely 

 formed of one or a few species of trees are entirely wanting. 



The vegetation which covers an area where the primeval forest has 

 been destroyed is utterly distinct from that of the latter, with its rich 

 and specialised primitive forms. The species thus establishing themselves 

 are quite different and are mostly those which have an extensive geographi- 

 cal distribution. I have adopted the tefm " secondary forest " for this 

 assemblage of vegetation, when, as is often the case, it is formed of timber 

 trees, which, however, never attain the size of those which constitute 

 the primeval forest. From a botanical point of view I cannot insist 

 too strongly on the difference which exists between these two kinds of 

 forest. 



Secondary Forest. — This kind of forest in Sarawak is characterised 

 by trees of small size, among which predominate the Etiphorbiacece 

 with the genera Mallotus and Macaranga ; some Ficus and other Urti- 

 cacece (Sponia, Pipturus, Leucosyke) ; and shrubs such as Eurya, Adinandra 

 Glochydion, Phyllanthus, Pavetta, Musscsnda, Callicarpa, Memecylon, 

 Melastoma, etc., amongst which various creepers trail their flexible 

 stems, mostly belonging to the genera Uncaria, Tetracera, Artabotrys, 

 Uvaria, Vitis, etc., together with some ferns. Amongst the small trees 

 of the secondary forest in Sarawak a composite of the genus Vernonia 



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