233 



because there was no shade and little food. Plants, whose distribution is 

 undoubtedly effected by birds, were already found by Ernst. Mr. Docters 

 van Leeuwen also found fairly great numbers of such plants. But still 

 most of the new plants are even now brought by winds and sea. It is not 

 feasible to state the exact way in which each plant arrived because comparat- 

 ively few positive data are available to us and many kinds of plants may be 

 distributed in more ways than one. In the first appendix to his paper Mr. Docters 

 van Leeuwen has stated the manner of spreading with the nearest 

 approach to accuracy he could, but often he has been compelled to guess *). 

 Besides these two main questions (treated of in 16 and 17) there are a few 

 of less importance. One of these, the spread of Cocos nucifera, Mr. Docters 

 van Leeuwen has already touched upon in passing. Another point inviting 

 investigation was to him the presence of a great number of galls. This sub- 

 ject was separately discussed by him *). 



As I have already repeatedly stated, nothing at all is known of 

 the vegetation or the fauna of the higher parts of Krakatao before 

 1908, nor of the manner in which the plants possibly introduced into 

 the interior after the eruption, have arrived there. We do not even 

 know whether any plants were survivors of the eruption. There is 

 no proof that birds have really introduced plants. Of course they 

 may have done so, but nobody knows it with certainty. It is not 

 proven that the wind has carried fruits, seeds or spores to Krakatao. 

 This may have happened, especially with the minute spores of the 

 Cryptogams and seeds of orchids it is highly probable but there has 

 been made not a single experiment, not even a single observation in 

 corroboration of this statement. As Mr. Docters van Leeuwen 

 correctly says, it is impossible to state the manner and way of intro- 

 duction. Nevertheless he has in Appendix I to his paper freely ventured 

 forth guesses on this point. Such guesses do not in any way advance 

 science. On Cocos nucifera I set forth my views already on p. 39 here- 

 before. Of the (afterwards to be discussed) paper on galls referred to 

 by Mr. Docters van Leeuwen, I will at present only say that 

 it contains nothing that brings us nearer to a solution of the problem. 

 Some galls have been found and in some way described, but the life- 

 history of the animals living in them was not studied. No observations 

 as to modes of transport have been made, but only remarks borrowed 

 from others or vague speculations without any scientific value. 



18. In this final paragraph Mr. Docters van Leeuwen makes some remarks 

 on the fauna, for the greater part admittedly borrowed from the paper of 



1 ) The Dutch text has here quite another reading: ,,ik heb bij benadering de ver- 

 ,,spreidingswijze aangegeven, doch ik heb er dikwijls een slag naar moeten slaan". i. e.: ,,l 

 ,,have roughly stated the manner of spreading but I was often compelled to make 

 ,, hazardous guesses". 



'-) Dr. W. Docters van Leeuwen. The Galls of Krakatau and Verlaten Eiland 

 in 1919, in Ann. |ard, Bot, Buitenzorg XXXI (1921), p. 57. 



