CHAPTER II 



THE FLORAS OF THE PACIFIC ISLANDS FROM THE STANDPOINT 

 OF DISPERSAL BY CURRENTS 



The initial experiment. The proportion of littoral plants. The two great 

 principles of buoyancy. The investigations of Professor Schimper. The 

 investigations of the author. The great sorting process of the ages. 

 Preliminary results of the inquiry into the buoyancy of seeds and fruits. 



IN the previous introductory chapter some of the numerous 

 questions affecting insular floras were briefly referred to. I will 

 now ask my reader, if he has had the patience to read it, to con- 

 sign that chapter for the time at least into oblivion, and to proceed 

 with me to our Pacific island with the intention of investigating 

 its flora from the standpoint of dispersal. We will together take 

 up the subject de novo, after banishing from our minds all 

 preconceptions that we may have possessed. 



After having been over the island gathering specimens of all 

 the seeds and fruits, we return to our abode on the beach. But we 

 are puzzled where to begin. The problem presents itself as a 

 tangled skein, and our difficulty is to find an " end " that we can 

 follow along with some chances of success. In our trouble we 

 look around us ; and at that moment we see a number of floating 

 seeds and fruits carried by the current past the beach. This 

 presents us with a clue and our investigation begins. 



We place all our seeds and fruits in a bucket of sea-water and 

 notice that many of them sink at once. In a few days we look 

 again and observe that many more are at the bottom of the bucket, 

 only a small percentage remaining afloat. We then remark to our 

 surprise that nearly all of the floating seeds and fruits belong to 

 coast plants, those of the inland plants, which indeed make up the 

 great bulk of the flora, having, as a rule, little or no buoyancy. 

 After a lapse of weeks and months the seeds and fruits of the 



