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sidering that the forests in the higher parts of the mountain differ 

 from those beneath in age, density and humidity, taking into account 

 that the walls of the ravines in which these forests are growing are 

 often almost perpendicular and fit only for a kremnophytic vegetation 

 which has nothing to do with forest but may develop on any 

 steep not too dry neither too sunny bank and not forgetting that 

 Krakatao has been frequently visited by man and has been inhabit- 

 ed during more than two years by many people (which fact must 

 have influenced the vegetation) we can expect beforehand that 

 the real forestplants of Mr. Docters van Leeuwen will prove 

 to belong to very divers oecological groups. This preopinion is 

 fully confirmed by the list given in Appendix III, which, even after 

 those ,,forest-plants which are no real forest- plants" have been 

 excluded, still consists of very heterogeneous elements many of 

 which are no forest-plants at all. 



To begin with, No. 55, Citrus spec., is certainly no forest-plant. 

 In Java there occur no species of this genus in a truly spontaneous 

 state. No. 28. Equisetum debi/e Roxb., is likewise no forest-plant at 

 all, much less a ,,real forest-plant". Mr. Docters van Leeuwen 

 himself found it on a slope bearing but a meagre vegetation. The 

 plant requires much light and though sometimes occurring on the 

 borders of light woods and in glades never penetrates into the forest 

 proper. No. 7, Nephro/epfs exaltata Schott and especially the form 

 recorded by Mr. Docters van Leeuwen as N. hirsutula Presl, 

 is a fern of grassy wilds and low sunny thickets. Mr. Docters van 

 Leeuwen himself admits that he found this ,,forest-plant" mostly 

 in little shadowed localities. No. 27, Ophiog/ossum reticulatum L., a 

 plant of badly pervious soils is rather frequently found in teak-forests, 

 but much more often on road-sides, on premises and lawns, on the 

 small grass-clad dikelets (galangans) between rice-fields and often also 

 above such nests of white ants, as are covered on their upper side 

 with an impervious layer of clay. It has no right at all to be called a 

 ,,real" forest-plant. No. 4, Dryopteris setigera O.K. is a kremnophyte of 

 sunny or moderately shadowed not too dry localities; it is often found 

 on almost perpendicular water- and road-sides and is certainly no real 

 forest-plant. No. 5, Aspidium melanocaulon BL, likewise a kremnophyte, 

 but of more humid and well shadowed localities is often found on 

 steep sides of water-courses and in native villages on the margins of 

 wells. Though it may be found in forests it is certainly no typical, 

 no real forest-plant. - No. 24, Lygodium circinatum Sw., a plant of 



