66 A NATURALIST IN THE PACIFIC chap. 



floating capacity of the fruit or seed. Finally he ascertains the 

 home of the plant. He does this for all the littoral plants with 

 buoyant seeds or fruits, and he forms his own conclusions of the 

 efficacy of the currents independently of the current-chart, 

 remembering that he has in Time an important factor that the 

 geographer does not possess in dealing with the currents. The 

 effect of time has often been to obscure the differential results of 

 the operations of the currents in the case of those species that, like 

 Barringtonia speciosa, are almost universally distributed in the 

 islands of the Pacific. It is obvious that such plants cannot aid 

 us much in the matter of ascertaining the track followed by the 

 drifting seed in entering this ocean. But if we find a littoral 

 plant with buoyant seed or fruit that has only partially performed 

 the traverse we shall possess in the interrupted operation an 

 important piece of evidence. 



Several years ago, -in my paper on Polynesian plant-names, read 

 before the Victoria Institute, I developed this argument when 

 endeavouring to find in the floating seed a clue to the route 

 pursued by the Polynesians in entering the Pacific. Since that 

 time my acquaintance with these islands and their plants has been 

 considerably extended ; but no important modification of the 

 principal argument is now needed. It was then pointed out that 

 in Nipa fruticans, the swamp-palm of the Malayan Islands and of 

 tropical south-eastern Asia, we have a plant well fitted for the 

 purpose and one well known to be dispersed by the currents over 

 small tracts of ocean. The Nipa Palm has attempted to enter 

 Polynesia from the Malayan region by two routes, namely, by 

 Melanesia and by Micronesia. Along the first route it has in the 

 course of ages reached the Solomon Islands, where I found it in 

 1884. Along the second route it has extended its range to Ualan 

 at the eastern end of the Caroline Group, where it was observed 

 by Kittlitz many years ago, as indicated in the narrative of his 

 voyage {Reise nacJi russische America^ nach Mikronesien, etc., 1858, 

 ii. 35), and in Dr. Seemann's English edition of the same author's 

 Vierundzwmizig Vegetationsansichten .... des stillen Oceans. 



The question now arises as to which of these two routes was 

 taken by the drifting seed. In my paper I adopted the view that 

 the shore plants reached Fiji and Samoa by Micronesia, that is to 

 say, by the Caroline, Marshall, and Gilbert Groups. This is the 

 route which, as mentioned by Mr. Hedley in the paper above 

 quoted, Mr. Woodford prefers for some of the Lepidoptera ; and it 

 is the one that is favoured by Mr. Wiglesworth for the birds, since 



