INTRODUCTION. 



Whenever we have been furnished Plus qu'ailleurs, le botaniste dans un 



a fetish and have been taught to be- pays tropical doit se munir de prudence 



lieve in it, and love it and worship it, et de methode dans ses recherches. 



and refrain from examining it, there Mieux vaut, dans ce cas, etre trop 



is no evidence, howsoever clear and sceptique que de ne I'etre pas assez. 



strong, that can persuade us to with- TREUB. 

 draw from it our loyalty and our 

 devotion. MARK TWAIN. 



The volcanic island Krakatao, in August 1883 devastated by a 

 terrific eruption, has greatly interested botanists and zoologists 

 ever since Treub in 1888 ') published the results of his botanical 

 excursion to that island in 1886. This almost universal interest was 

 due to the fact that, on the authority of Treub, it was considered 

 an irrefutable truth that the original flora and fauna of Krakatao 

 had been wholly destroyed by the eruption. Hence it was thought 

 that Krakatao presented the ojeedingly rare occasion of tracing, 

 step by step, how the flora and fauna are restored on an island, 

 entirely deprived of its animal and vegetable life. 



Treub 2 ) already was perfectly aware that in this question the 

 cardo quaestionis lay in the word ,,how". Considering what may be 

 daily observed on coral-islands it might safely be expected that, 

 after some lapse of time, plants and animals would reappear on 

 Krakatao. Not in this expectation itself did the interest of the 

 scientific world concentrate, neither in the fact of its fulfilment. But 

 confining ourselves to the botanical side of the problem, the all- 

 important questions were: When will plants reestablish themselves on 

 Krakatao ; which species will be the first to arrive, which will fol- 

 low; from where will these plants come; in which form (seeds, spores, 

 grown-up plants) and by which expedient will they cross the sea; 

 at which point of the island will they arrive; which possibilities or 

 difficulties of existence will be offered by the spot reached by them; 

 will they, under the combined influence of soil and climate, either 

 thrive and develop or come to a standstill and die out; which 

 associations will they form; how will they, mutually, keep up the 

 struggle for life, assist each other in that struggle or, perhaps, 

 gradually make their own existence impossible; which phases of 



1 ) Ann. lard. Bot. Buitenzorg, line Serie VII (1888) 213 seq. 



2 ) Ann. jard. Bot. Buitenzorg, Ime Serie VII (1888) 213: , parce qu'on 



ne sait absolument rien sur la maniere dont He volcanique se recouvre d'une vegetation 

 entierement nouvelle". 



