Nov., 1918] Recovery of Vegetation at Kodiak 9 



bodily into the crater of Katmai. In the present case, the area 

 covered by deep deposits, through which the roots of plants 

 can not reach the original soil, is more than a hundred times as 

 large. 



Unfortunately, moreover, the study of Krakatoa was of a 

 very fragmentary nature. It was three years after the eruption 

 before the island was visited at all. Revegetation had already 

 begun on an extensive scaled This first plant life consisted 

 of blue-green algse and ferns, but several species of seed plants 

 were already well established. After this first brief visit 

 no other observations are recorded for eleven years, until 

 1897 when it was visited by Penzig^ After this visit, a similar 

 period elapsed before another visit, that of Ernst^ and CampbelP. 

 Although Ernst has worked up the data gathered, in masterly 

 fashion, it should be remembered that his opportunity for field 

 examination was very brief, consisting of only a few hours, 

 during which time it was not possible so much as to reach the 

 summit of the island, much less to explore it carefully. 



These workers, moreover, paid little attention to the 

 problem which most concerns us, namely, the means of prepara- 

 tion of the raw inorganic soil for the life of higher plants, 

 but studied especially the means of dispersal by which the 

 plants reached the new land, making the observations the 

 basis of a study in plant distribution for which Krakatoa, by 

 virtue of its insular position, offered a unique opportunity not 

 duplicated at Katmai. 



Since these papers are well known to most botanists, there 

 is no occasion to abstract them at length here. Probably 

 the most significant of the results brought out are the following : 

 (1). The pioneer vegetation consisted not of flowering plants, 

 but of Blue-green algae (Cyanophyceae), which were followed 

 by ferns and then by flowering plants. (2). The first flowering 

 plants were species whose seed was either distributed by the 

 wind or by ocean currents, invasion progressing largely from 

 the strand. (3). It was believed that the nitrogen compounds 

 necessary for the growth of the luxuriant vegetation were 



" Treub, M. Notice sui la nouvcUe Flore de Krakatau. Ann. Jard. Bet. 

 Buitenzorg 7: 213-22.3. 1888. 



^ Penzig, O. Die Fortschnitte der Flora des Krakatau. Ibid 21 : 92-113. 1902. 



* Ernst, A. The New Flora of the Volcanic Island of Krakatau. Translated 

 by A. C. Seward. Camb. Univ. Press. 1908. 



3 Campbell, D. H. The New Flora of Krakatau. Am. Nat. 43: 449-460. 1909. 



