320 A NATURALIST IN THE PACIFIC chap. 



common to two groups. Thus, Hawaii and Tahiti each have their 

 own species. Rarotonga, according to Cheeseman, owns a peculiar 

 but not yet fully described form. Samoa has two and Tonga has 

 one species. Westward from Tonga and Samoa the numbers 

 of species increase, Fiji possessing five and New Caledonia four. 

 Australia and New Zealand each claim two species as their own. 



Dr. Warburg, who has studied the genus in its home, remarks 

 on page 43 that none of the species possess any means of dispersal 

 enabling them to cross an ocean ; and he connects with this 

 the fact that the genus is only found (to use his own words) 

 on islands like those of Samoa, Tahiti, and Hawaii, that possess a 

 " palseobiotic '' nucleus {jpaldobiotischen Kern), and not on islands 

 like the Bonin Islands of new formation {auf Neubildungen). 

 This attitude towards the problem of plant-distribution in the 

 Pacific is backed by a great experience ; but it is one, of course, that 

 is directly opposed to the line of argument followed in these pages ; 

 and it is needless to say that it is not encouraging to the student 

 of plant-dispersal. Yet one could hardly look upon the islands of 

 the Tongan Group with their representative of the endemic 

 Freycinetias as of more ancient origin than the Bonin Islands that 

 have none ; and plants that find their homes on the peaks and in 

 the forests of mountainous islands would rarely find a suitable 

 station on the low coral islands of the Pacific. It is, however, 

 noteworthy that Professor Schimper is inclined to include a species 

 of Freycinetia as amongst the strand-flora of the coral islands of 

 the Java Sea {Ind. Mai. Strand-flora, p. 1 34). With regard to the 

 question of the means of dispersal of Freycinetias, it will at once be 

 shown that these plants possess many opportunities for dispersal 

 by birds. 



Though in our own time dispersal by birds between the various 

 Pacific archipelagoes is often largely suspended, the inter-island 

 dispersal in each group is usually active through the agency of 

 birds, now like the plants they distribute confined to each group. 

 Thus with Freycinetia we find that, notwithstanding that each 

 Pacific group is, as regards this genus, isolated from the others, the 

 separate islands, as in the case of those of Hawaii, may possess 

 a common species dispersed over the area. The ripe fruit, which 

 consists of a number of berries in a head or spike, is juicy and 

 pulpy, and contains in each berry a large number of minute oblong 

 or fusiform seeds, usually one or two millimetres long and possess- 

 ing thick toughish tests. Birds, indeed, are fond of pecking at the 

 ripe fruit-heads in Hawaii. Thus we learn from the Aves Hawaiienses 



