28 



the vegetation of these ravines were obtained and these data strongly 

 prove for the correctness of my views. When Ernst, P u 1 1 e, 

 Campbell and myself in April 1906 approached Krakatao from its 

 southern side we distinctly saw how the Barringtonia- and Casuarina- 

 associations formed a narrow strip along the shore. Behind this 

 strip extended a broad grass-jungle with scattered trees. But in the 

 upper half of the mountain several ravines were clothed with woods 

 running up high against the cone; the upmost ridges and the top 

 bore scattered trees. These forests in the ravines are considered 

 by me to be rests of the old vegetation or the off-spring of these. 



As one may read in E r n s t's publication ') we did not succeed 

 then in reaching these higher ravines In the short time at our dis- 

 posal and with our very defective equipment we could not pene- 

 trate the broad, very dense, 3-5 m. high grass-jungle-), despite of 

 the utmost exertions. 



But during the expedition in 1908 my companions and I reach- 

 ed a height of + 400 m. and at the same time the ravine-forests, 

 at the height of 200 400 m. still rather young and, so to say, form- 

 ing the vanguard of the older, further developed woods in the 

 higher parts :i ). In the very few ravines I had occasion to search, 

 this young forest mainly consisted of Ficus fistti/osa Reinw., Ficus 

 fulva Reinw., Ficus toxicaria /../and Homalanthus populnea O. K. with 

 an undergrowth of Leucosyke capitellata Wedd., Cyrtandra sulcata 

 B/., Heckeria umbelliita Ktti. var. subpeltata. D. C., Leea indica Merr. 

 and SeJagine/ld plana Hicron. All of these plants are frequent in forests 

 at low altitudes in West-Java; it is quite possible that they were 

 growing on Krakatao before 1883 and survived the eruption. Only a 

 single day being available in 1908 for the botanical investigation of 

 this side of the mountain, it necessarily was very fragmentary and 

 superficial. Referring to what I have said on pp. 5 and 6 about the 

 composition of unstable vegetations in the tropics, I think it quite 

 possible, even very probable, that in other ravines than those searched 

 by us, or in the higher parts of these, the young forest consisted 

 entirely or partly of other plants. That in 1919 several species were 

 collected on Krakatao that had not been found in 1908, is by no 



l ) Neue Flora Vulkaninsel Krakatau (1907), p. 33. 



-) This jungle consisted mainly of Saccharum spontaneum L. junghuhn (See 

 Chapter VI) gives a vivid description of such a iac-c/iaru/n-jungle. 



*) Fransen Herderschee [laarverslag Topogr. Dienst Ned. Indie. (Year-book 

 of the Topographical Survey Service in the Dutch Indies) 1908, pp. 156,157] found in 

 the lower ravines trees of 1.0 15 , n . height. In the higher ravines the trees were 

 taller (up to 20 m ). Hence it is probable that the vegetation has proceeded from 

 above downwards. 



