xxvi EUGENIA 



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been brought by birds. Thus, on the bare surface of a large block 

 of tuff forming the highest peak of Koro-Mbasanga, 2,500 feet 

 above the sea, I found only two plants, Oxalis corniculata and a 

 species of Peperomia. 



EUGENIA (Myrtaceae). — This is a very extensive genus split up 

 into different subgenera, and comprising some 600 or 700 known 

 species scattered over the warm regions of the globe. Their 

 fleshy, usually red, berries contain as a rule one or two large seeds, 

 and attract birds and animals of all descriptions. The feature 

 most interesting to us is the dispersal of the genus over the Pacific 

 islands eastward to the Low Archipelago and northward to Hawaii. 

 The track by which it has entered the Pacific from the west is 

 indicated in the distribution of the species. The genus is only 

 well represented in the Western Pacific, whilst eastward and 

 northward of Samoa and Tonga the distribution is fitful and 

 irregular, it being evident that the extension beyond these two 

 groups has been accomplished with difficulty. 



There are at least twenty-five species in Fiji, of which perhaps 

 half would be peculiar; in Tonga eight species, of which two may 

 be endemic ; in Samoa thirteen species, of which four are peculiar; 

 in Rarotonga none ; in Tahiti a single non-endemic species ; and 

 in Hawaii two species, of which one is peculiar. Only truly 

 indigenous species are here recorded, and Eugenia malaccensis, 

 which has accompanied the aborigines in their migrations, is not 

 included. A solitary species, E. rariflora, connects together all the 

 principal archipelagoes from Fiji to Tahiti and the Gambier 

 Islands, and northward to Hawaii. Nine species are known to be 

 common to the region in which lie the three groups of Fiji, Tonga, 

 and Samoa ; and since some of these species occur in the groups 

 further west they may be regarded as keeping up the connection 

 with the original home of their ancestors in the Malayan region. 



Looking at these facts of distribution of the genus Eugenia 

 in the open Pacific, it is evident that whatever dispersal of the 

 genus is now in progress in this ocean is mainly confined to 

 an interchange between the groups of Fiji, Tonga, and Samoa 

 in the Western Pacific, and doubtless between the islands further 

 west of these groups. The smaller islands lying between and 

 around these three groups participate in the distribution of the 

 species common to all. Thus Wallis Island, according to Drake 

 del Castillo, possesses two of these species. Over the rest of 

 the ocean the dispersal of the genus seems to be no longer 

 effective, since Eugenia rariflora, which links together Fiji, Tahiti, 



