171 



present knowledge goes this last supposition seems to be baseless. 

 Perhaps the humidity of the climate is also of some influence. Most of 

 the Indian Leguminosae are inhabitants of dry regions. Neverthe- 

 less even in regions where the east-monsoon is so feeble as in 

 Buitenzorg several Leguminosae occur in a wild state (i.a. Alysicarpus 

 nummularifolius D.C., Cassia Leschenau/tiana D.C. and Tora D.C. 

 Crotalaria incana D.C. and striata D.C., Desmodiuni heterophyHum 

 D.C:., and triflorum D.C., Mimosa pudicj L,~ Phaseo/us sublobatus 

 Roxb, and several others), some of these even in great numbers. 

 As late as 1919 none of these species had been found on Kra- 

 katao. 



The short time that in 1906 could be given to the exploration 

 was insufficient for a close investigation of the vegetation of algae. 

 Bluish green algae were seen in the interior on the south-eastern side 

 but we do not know to which species they belonged. We know 

 nothing of the vegetation of algae on the pumice- and ash-fields above 

 Zwarte Hoek; probably it had been locally superseded by higher 

 plants and was present only on naked walls and such-like localities. The 

 two new Polyporaceac were growing on a tree-trunk washed ashore 

 but this is of course no proof that they were introduced in this manner. 

 Their spores may quite well have come after the tree. Many other 

 fungi may in 1906 have been present in the humid higher ravines; 

 we do not know whether they were introduced after the eruption and 

 if so, in which manner; their spores may very well have been carried 

 over by the wind, but there exists no proof for this, it is only d 

 plausible guess. Seventeen of the species ') found for the first time 

 in 1905 or 1906 are plants which, in the Dutch Indies, are generally 

 found on the beach and the localities immediately behind it. All these 

 species have a wide distribution along the coasts and may have 

 grown on Krakatao long before 1906. Without exception they possess 

 seeds or fruits fit to be spread by sea-currents, hence it is very 

 probable that they were imported by the sea. The nutlets of Hyptis 

 brevipes Poit. (in Java a very common Labiata of watersides and rice- 

 fields) which in 1905 had been found on Krakatao by Vale ton (habitat 

 not mentioned) and was collected in 1906 at the very base of the 

 basaltic rocks, possess floating power. These nutlets or fruit-bearing 



l ) Clerodendron inerme Gartn., Co/umella tri folia Merrk Cycas rumphii Miq., 

 Dem's heterophylla Backer, Desmodium umbellatum D.C., Dodonaea viscosa lacq , 

 Guettarda speciosa L., Indigofera zollinqeriana Miq., Ipomoea denticulate Chois., 

 Ipomoea long/flora R. Br., Pithecolobium umbellatum Bth., Pongamia pinnata Merr., 

 Prernna integrifolia L., Remirea maritima Aubl., Sophora tomentosa L., Thespesia 

 populnea Soland., Xylocarpus granatum Koen- 



