152 A NATURALIST IN THE PACIFIC CHAP. 



2 inches (37 to 50 mm.), and so dry and unattractive for birds, that 

 any other agency but that of the currents appears to be out of the 

 question. 'Indeed their dry appearance would suggest to my 

 readers that only birds of the habits of the ostrich would venture 

 on such a diet. It is, however, worth noting that whilst in the 

 Keeling Islands I learned that a cassowary that had been kept on 

 the atoll was a very efficient distributor of the seeds of Ochrosia 

 parviflora, scattering the undigested stones everywhere, and causing 

 the young trees to become so numerous that they had to be 

 destroyed. A similar habit of the cassowary in the Aru Islands is 

 recorded by Beccari, where the dry fruits of a palm, 2j inches 

 across, are swallowed by these birds and the seeds dispersed. 

 Cassowaries are active agents in dissemination, for they swallow 

 every kind of pulpy fruit, and convey them long distances 

 undigested ; they are also excellent swimmers and traverse 

 considerable expanses of water (Beccari, quoted in Chall. Bot., iv., 



297, 313). 



Modern ornithologists would probably not object to our appeal- 

 ing to the former volant habits of the cassowary and its allies even 

 across a wide tract of sea ; but, excepting in New Zealand and its 

 vicinity, such birds are not at our disposal in the island groups of 

 the open Pacific. There is a possibility that the extinct Columbse 

 and other exterminated birds of the Mascarene Islands might 

 account for some anomalies in their floras ; and in Chapter XVI. 

 reference is made to the fact that these islands possess more 

 endemic species of Pandanus than any other oceanic groups, 

 a genus possessing drupes that in the case of inland species seem 

 unfit for any mode of dispersal with which we are familiar. In the 

 islands of the tropical Pacific, however, it is not possible to find 

 such a way out of the difficulty, since, as shown in Chapter XXX 1 1 1., 

 the birds are lacking. 



The genus, according to the Index Kewensis, includes about 

 ten species distributed over the islands of the Indian Ocean, and 

 found also in Malaya, Australia, and throughout the Pacific. It is 

 essentially an insular genus, and two at least of the species are 

 wide-ranging littoral trees, one, Ochrosia borbonica, mainly dis- 

 tributed over the islands of the Indian Ocean and of Malaya, 

 and the other, O. parviflora, chiefly of the islands of the Pacific. 

 It will be out of place to deal here in any detail with this 

 interesting genus, and my remarks will be confined to such matters 

 as concern the origin of the inland species of the Hawaiian Islands, 

 species that are peculiar to that group. Some confusion has pre- 



