222 



seeds of non-littoral plants washed ashore may, after having dried, 

 be driven by the wind to salt-free localities in the interior and 

 germinate there ') It ' s clear that the problem of the settlement 

 of new plants introduced by the sea is much more complex than 

 Mr. Docters van Leeuwen but for a moment supposes. 

 But as all investigations on Krakatao on this subject are entirely 

 lacking, it is needless to further discuss the matter. 



^ II- In this paragraph the excursion of 1897 is discussed. Pen:ig and his com- 

 panions found the flora much enriched and, what was most remarkable, plant- 

 communities (of which term Mr. Docters van Leeuwen gives a definition) 

 had already been formed. Penz ig distinguished 3 formations: that of the 

 beach-plants, the Rarrincjtonia-formeition and that of the grassy wilds. 



Penzig's paper was already discussed in Chapter VI to which 

 I refer. As to the first formation of plant-communities, see p. 90. 

 Mr. Docters van Lee u wen's nomenclature of the strand-forma- 

 tions is somewhat obscure. He distinguishes between beach-plants 

 and the Biirriinjtonia-formation, forgetting that the latter also consists 

 exclusively of beach-plants. This Harringtonia-iormation may either 

 border immediately on the sea or be secluded from it by the Pes caprae- 

 formation. This depends on the nature of the beach; on decreasing 

 beaches the Pes Ccjp/-c?e-formation is very often lacking whilst on 

 increasing sandy -) beaches it is as a rule, present. It seems that by 

 the name of beach-plants Mr. Docters van Leeuwen meant to 

 indicate only the /Vs caprae-iormat'ion. Besides the 3 formations 

 mentioned by Mr. Docters van Leeuwen, Penzig found a 

 fourth, the (kremnophytic) vegetation 3 ) of ferns growing on the steep 

 sides of the rocks. The /Ja/T/ngtom'u-formation was found by Penzig 

 only on Verlaten Eiland: it consisted of a grove of young specimens 

 of Casuarina equisetifolia L. 4 ), 5 6 m. high. Four years afterwards 

 H a e c k e 1 5 ) observed on the coast of Krakatao a small grove which 

 seemed to reach a height of 1015 m. As to the components of 

 this grove one can only guess. I shall refrain from doing so. 



*i 12. In 1906 Ernst and his companions visited Krakatao. The formation of plant- 

 communities had made further progress; the number of plants had vastly 

 increased. Ernst records for the 3 expeditions together 108 species 6 ) for 

 the whole Krakatao-group. I he majority of these plants belonged to the 



') See p. 12, footnote 1. 



-) Increasing clayey beaches bear, as a rule, mangrove-forest. 



") See p, 31, 



4 ) See pp. 125 and 205. 



5 ) See p. 27, footnote 3. 



'') This is indeed the total number of Phanerogams and ferns recorded by Ernst, 

 in which the finds of Vale ton (See Chapter VII) are not included. After the necessary 

 corrections have been made, this number of 108 is reduced to 96. 



