99 



chapter VIII). On Cocos nucifera L. I gave already my views on pp. 

 39 seq. P e n z i g found nuts washed ashore but does not mention 

 to have seen germinating nuts or young trees. 



On the beach at Zwarte Hoek P e n z i g and his companions 

 found several seedlings which furnished proof that a great part of 

 the seeds washed ashore were able to germinate. It is much to be re- 

 gretted that P e n z i g does not mention the names of these seedlings 

 which he rightly considered to be instructive Beweisstiicke", and 

 which were collected with ,,besonderem Eifer". For the problem of 

 revegetation they certainly were of much more importance than the 

 seeds which had not yet germinated. 



After having examined the beach the visitors penetrated into 

 the interior of the island. In order to do so they had to ascend the 

 rocks of Zwarte Hoek; everywhere else the beach is secluded from 

 the interior by an unscalable wall. These same rocks were in 1886 

 examined by T r e u b. As they cover a rather large area, offer many 

 difficulties to the investigation (see p. 29) and the whole exploration 

 in 1897 was of but half a day's duration, they could be examined 

 but very cursorily. Moreover, it is not at all certain that the part 

 of the interior examined in 1897 was really identical with that of 

 1886, that the party followed quite the same route as Treub had 

 done 11 years before. Referring to what I have said on pp. 5 7 

 on the great local differences a young vegetation may show I need 

 scarcely argue the necessity of being very cautious when comparing 

 the results of 1897 with those of 1886. 



On the hills investigated and in the shallow valleys between, 

 the vegetation, according to P e n z i g, consisted in 1897 almost 

 exclusively of three tall grasses, viz. Pennisetum macrostachyum 

 Brongn. (Gymnothrix elegans Biise, see p. 48, No. 8), Saccharurn 

 spontaneum L. and Neyraudia madagascariensis Hook. fit. var. Zo/- 

 lingeri Hook. fit. (in Penzig's paper mentioned under the name of 

 Phragmites Roxburgh!! Steud.)- In the dense jungle formed by these 

 grasses other plants occurred only in scattered specimens. The 3 

 grasses named collectively by Penzig are by no means oecologic- 

 ally equivalent; in 1897 they were doubtless not present in almost 

 equal numbers, neither nearly regularly dispersed. Pennisetum macro- 

 stachyum Brongn., easily recognizable by its drooping, caudiform, 

 white or yellowish spikes, is a perennial, tillering grass, \ l /^3 m. 

 high, with a short, not very deeply buried rhizome; old specimens 

 form small tussocks. This species grows only in sunny and often rather 



