65 



The identity of the 3 other Compositae is not established but it 

 is certain that they all possess a pappus on the fruits. From this, 

 however, by no means follows that these fruits had been carried by 

 wind across the sea for length of at least 20 km., the distance by 

 which Krakatao is separated from the island Sebesi, the nearest point 

 of which it is sure that the vegetation in 1883 was not entirely 

 destroyed. As I have set forth on pp. 50 52 Treub must have 

 found 3 out of the there-mentioned 5 species. Three of these five 

 (Blumea balsamifera D. C., Erigeron Hnifolius Willd., Pluchea indica 

 Less], perhaps also the 2 other ones, may quite well have grown 

 before the eruption in or near the locality investigated; their fruits 

 and even the subterranean parts of some of them may, in well- 

 sheltered spots, have survived the catastrophe. If one will insist on 

 introduction having taken place from outside, one should bear in 

 mind that these 5 Compositae are quite common in West-Java and 

 may occur also in South Sumatra. Their fruits may very well have 

 been carried by flowing rain-water to the rivers and by these to the 

 sea; they may also have been driven by wind straight into the sea. 

 The sea may have washed them ashore at Zwarte Hoek and, after 

 they had become dry, the wind may have driven them into the 

 interior ') Hrnst has argued on very good grounds -) that transport 

 by water from Java to Krakatao can be made within a single day and 

 it has never been proven that the fruits of the Compositae mentioned 

 have lost their germinative power after having floated for a day on 

 sea-water. Moreover the possibility exists that the many visitors 

 who came to Krakatao after the eruption but before Treub's 

 investigations have carried over fruits on their clothes or with their 

 things. Finally, fruits may have been introduced by native vessels 

 landing at Krakatao, by driftwood, by pumice, by birds. There does 

 not exist the faintest shadow of a proof for direct introduction by 

 wind. Hence I can by no means share the opinion of S c h i m p e r :i ) 

 and Ri k I i '*) that the possibility of direct transport of seeds and fruits 

 by wind for a long distance across the sea is ,,endgiiltig nach- 

 ,,gewiesen" by Treub's investigations. These investigations or, to 

 speak the plain truth, guesses, lack all conclusive force. 



J ) The beach at Zwarte Hoek is for the greater part secluded from the interior 

 by a steep wall- In the most north-western part however the lower basaltic slopes are 

 easily accessible from the beach. 



2 ) Neue Flora Vulkaninsel Krakatau (1907), p. 56. 



s ) Sc hi in per, Pflanrenqeographie (1908), p. 90. 



*) Rikli, Richtlinien der I'flanzengeographie in Fortschr. Naturw. Forschung III 

 (1912), p. 260 



