31 



growing by preference on steep walls and, apparently, better fit than 

 other ones to grow in little weathered, hard, sterile localities, lacking 

 in humus I shall indicate in future by the name of kremnophytes 1 ). 

 To the Javanese kremnophytes of the lower, not too dry regions, 

 belong, besides a number of algae, mosses and lichens, especially ferns, 

 i.a. 1 Adiantum caudatum L., Adiantum lunu/atum Burm., Antrop/iyum 

 latifolium RL, Antrophyum reticulatum Kaulf., Aspidium me/anocau/on 

 Rl., Aspidium vastum B/., Blechnum orientale L., Ceropteris ca/ome- 

 lanos Llnd. Chei/anthes farinosa Kaulf., Chei/antlies tenuifolia S\\'., 

 Doryopleris conco/or Kuhn., Dryopteris arida O.A., Dryopteris 

 c-i/cu/Jufi] U/iw'sf., Dryopteris intermedia O.K., Dryopteris mol/is 

 Hieron., Dryopteris setigera O.K., G/eichenia laevigata Hook., 

 G/eichenia tinearis Clarke., Hemigramma latifolium Cope/., Lindsay a 

 cu/trata S\v., Nephro/epis exa/tata Schott., Onychium si/iculosum C. 

 C/ir., Odontosoria chinensis /. Sm., Po/ystichuni diaphanum Moore, 

 Pteris ensiformis Burm., Pteris vittata L., Schizo/oma ensifo/ium /. 

 Sm., Trichomanes /avanicum Rl. and several more 2 ). In sunny or slightly 

 shadowed localities Lycopodium cernuum L. and the grass Pogona- 

 t/ierum paniceum Hack are very common, the latter often clothing 

 vertical walls over large surfaces. Qldenlandia hispida Bth., Peperomia 

 pellucida Kth., Pi/ea microp/iyl/a Liebm. and, locally, Epit/iema saxati/c 

 Bl., Rhyncog/ossum obliquum Rl., Monophyllaea Horsfie/dii R. Br., 

 Begonia hirtella Link and Salornonia cantoniensis Lour are of rather 

 common occurrence on steep walls. Canscora diffuse R. Br. and 

 Soneri/a hegoniifo/ia Bl. are much rarer. Among the Orchidaceae 

 Arundina speciosa Bl. and Spathog/ottis plicata B/. belong to the 

 common kremnophytes. Before the eruption many of these species 

 may have grown on steep ravine-walls and unfertile ridges on Kra- 

 katao and some individuals may have survived the eruption, either 

 by their rhizomes or by spores or seeds, which began a new life as 

 soon as the ashes that covered them were washed away. 



It is remarkable but, from our point of view, easily accounted 

 for, that T r e u b who made his researches on the above-mentioned 

 slopes near Zwarte Hoek found there a rich fern-vegetation, composed, 

 in the main, of part of the species recorded above. Of the 1 1 species 

 of ferns collected by T r e u b, 2 are typical for swampy or at least 



*) Derived from Kpy/tvfa, steep wall, and QuTOV, plant. Cf. Backer en Van 

 SI oo ten, lavaansche Theeonkruiden, ('1924) p. 14. 



2 ^ These species are by no means oecologically equivalent, especially not as 

 regards their need of light and humidity. The species of Antrvphyum, Aspidium and 

 Trichomanes are heliophobic, those of Cleiclienia heliophilous. Consequently they are 

 never found together in the same locality. 



