Future Developments 71 



higher localities which have not, like those which we collected, come 

 from the strand vegetation and from the low-lying parts of adjacent 

 islands but from the higher regions of the Javan and Sumatran 

 mountains; plants with light seeds which have been carried from 

 the high volcanic cones of Java by strong winds which blow at the 

 higher altitudes, especially by the south-east winds which prevail 

 during the greater part of the year. Above all we may expect to find 

 in the future those wind-distributed and animal-distributed species 

 which in Java and Sumatra take possession of patches of ground in 

 which volcanic eruptions have destroyed all traces of vegetation. 

 In such situations, as Schimper 1 has shown in the case of Goenong 

 Goentoer and as I propose to describe 2 in a further account of 

 the colonisation of volcanic areas in Java and Sumatra (Gedeh, 

 Pangerango, Papandajan, G. Goentoer, Dieng and Tengger mountains 

 in Java, Merapi and Singalang in Sumatra), are found Grasses, Cypera- 

 ceae, Ferns, and Orchids, also shrubby and arborescent phanerogams 

 with wind-distributed seeds and fruits, especially species of Rhodo- 

 dendron and G)tapha/i><m, while other plants, Varcirnum, GauUeria, 

 Myriea, Aralia, etc., are distributed chiefly by birds. Many of the 

 latter plants which live in the forests as epiphytes, assume the habit 

 of ground-plants on a volcanic substratum where there is little com- 

 petition with other plants, and at a later stage, when the vegetation 

 becomes denser and arborescent plants occupy the ground, they revert 

 to an epiphytic manner of life. 



In the mountain forests, which extend both upwards and down- 

 wards, new conditions of life are produced. Spores of cryptogams and 

 seeds of phanerogamous plants, which have not as yet met with con- 

 ditions necessary for germination and growth, at a later stage form 

 new elements in the flora. Lianes, epiphytic mosses, ferns and orchids 

 make their appearance. The rocks on the mountain slopes become 

 clothed with liverworts and mosses in shady places, and lichens spring- 

 up in more sunny situations. The mycelia of mould-fungi and species 

 of the Phalloideae and Agaricineae flourish in the decaying leaves 

 on the ground of the forest. Possibly the bleached saprophytic 

 flowering plants and parasites may also obtain a footing on branches 

 and roots. 



Man plays no part either in opposing or accelerating this develop- 

 mental process. The west regions of Java, and the whole of the 

 southern regions of Sumatra are still sparsely populated ; many fertile 



1 Schimper, A. F. W. Pflanzengeographle, p. 201. [Plant Geography, p. 185.] 



2 Ernst, A. "Die Besiedelung vulkanischen Bodens auf Java und Sumatra." 

 To be published in Vegetationsbilder, by G. Karsten and H. Schenck, Jena, 1908. 

 7 Reihe, Heft 1 and 2. 



