XII, C, 4 Brown, Merril and Yates: Voleano Island 213 
It is a common observation that the upper slopes of active 
volcanoes are usually very bare, and this is frequently the case. 
even when there have been no recent eruptions, 
Schimper ** visited the voleano of Gunong Guntur in western 
Java many years after the vegetation had been completely des- 
troyed by an eruption and found the vegetation quite open and 
very poor. 
There are absolutely no trees, but shrubby and herbaceous plants of 
very various species were present. * * *, The most essential part was 
played by plants that grew as epiphytes in the neighboring woods, namely 
many orchids, as. well as several ferns and the shrubby Rhododendron 
javanicum, * * *, 
The picture that Schimper gives of this vegetation indicates 
that the ground was very largely bare and that, as on the larger 
part of Volcano Island, the plants were very scattered. 
Another interesting example of a sparse vegetation on a 
volcanic cone is afforded by the Gedeh in western Java. The 
active crater is a small cone within a much larger ancient crater. 
The slopes of the mountain and most of the ancient crater are 
covered by a dense and varied vegetation, while the slopes of 
the new cone, although signs of volcanic activity are very slight, 
show a very sparse vegetation. This mountain was visited by 
Brown and Yates in 1917. On the active cone there were 
present only the following 9 species of higher plants and ferns: 
Gaultheria nummularioides G. Don. | Anaphalis javanica Sch. 
Gaultheria leucocarpa Bl. Carex hypsophila Mig. 
Gaultheria fragrantissima Wall. Histiopteris incisa J. Sm. 
Rhododendron retusum Benn. Polypodium feeti Bory. 
Vaccinium varingiifolium (Bl.) Mig. : 
These include 5 Ericaceae, 1 composite, 1 sedge, and 2 xero- 
phytic ferns. These plants were very scattered and all were 
small, there being no specimen on the active cone that was more 
than 0.5 meter in height. The density of the vegetation was 
very similar to that shown in Schimper’s photograph taken on 
Gunong Guntur. rate! 
It seems evident that the invasion of soils of recent volcanic 
origin varies very greatly in different cases, and our present 
knowledge does not appear to justify us in trying to establish 
any general laws. 
* Schimper, A. F. W., Plant-Geography upon a Physiological Basis. 
Eng. trans. by W. R. Fisher. Clarendon Press, Oxford (1903). 
i 
