26 







history of the eruption itself may be concluded that the vegetation 

 of the island must have been entirely destroyed by heat or by 

 suffocation. On the contrary, everywhere in the higher regions where 

 the covering layer was but thin and soon washed away, where 

 on steep ravine-sides far projecting rocks sheltered the vegetation 

 beneath, moreover in deep hollows or crevices of precipitous cliffs, 

 lower soil-organisms, mycelia, spores, seeds, rhizomes, root-systems 

 and even entire plants, when not too large, may have survived. 

 They will undoubtedly have suffered from the drought, caused by the 

 soil having been somewhat heated, but after sufficient rain had 

 fallen, many remnants may have begun a new life. 



Consequently it is not in the least proven that by the eruption 

 of 188& the soil of Krakatao was everywhere thoroughly sterilized. 

 From the very first the researches were conducted by Treub in a 

 predefined and, in my opinion, wrong direction. As he positively 

 meant that the entire island had been covered with a permanent 

 thick layer of very hot eruptive products, he felt quite convinced 

 that all life had been destroyed and therefore considered it super- 

 fluous to assiduously seek for surviving rests of the old vegetation. 

 Had he known that his argument was based on a fallacy, the sharp- 

 witted savant would have acted otherwise. 



If, indeed, rests of the old flora have survived in the higher 

 ravines on the south- and south-eastern sides, we may presume that 

 these ravines have become starting-points of the new vegetation. 

 I he eruption took place towards the close of August, in the very 

 midst of the dry monsoon. On Krakatao the east-monsoon is, as a rule, 

 interrupted by repeated rains ') as appears not only from the ravines 

 having been deeply eroded already two months after the eruption, 

 but also from the present vegetation 2 ). Yet it is probable that 



] ) Of Krakatao Itself no definite figures about the amount of rain exist- In the 

 3 nearest rainfall-stations, Anjer Kidool Kalianda and Telok Betong, which all lie in 



the plains (see plate I), the 4 driest m 

 and 38.5 rain-days. Hence in the dry m 

 alternates with a rain-day. I he total an 

 that the mean fall per rai 



iths of the year 3 ). have together resp. 25.3, 33 

 nsoon, on an average, a period of 2 4 dry days 

 ounts in these 4 months are resp. 322, 428 and 

 -day (12V9 a 13 mm-) is by no means insign 



ficant. The supposition of Ernst [Neue Flora VulkaninsebKf akatau (1907), p. 50] that 

 on Krakatao, which rises up to above 800 in. and therefore most probably receives 

 more rain than the plains around, in the east-monsoon, rains are comparatively scarce, 

 is not probable, much less proven. 



2 ) This is testified by many facts : As late as in 1908 on the porous pumice-ridges 

 xerophytes did not or only most sparingly occur; Saccharum spontanrum was growing 

 gregariously on the ridges; Spathoglvttis plicata and ArunJina speciosa were copious 

 on steep ravine-sides; CyrtauJra sulcatii was numerous at a low altitude; many fungi 

 and epiphytic ferns and Orchidaceae have been found in the island. 



:1 ) Cf. Boerema, Rainfall in the Netherlands Indies (19251, pp. 2 and 164. 



