xxv GARDENIA 311 



inter-island dispersal still continues in the Hawaiian Group, the 

 species characteristic of that archipelago being found in all the 

 islands. 



Reynoldsia sandwicensis came frequently under my notice 

 in Hawaii, and the fairly fleshy drupes, about one-third of an inch, 

 or 8 millimetres, in size, with their crustaceous pyrenes appeared to 

 me well fitted for assisting the dispersal of the plant by frugivorous 

 birds. Yet here the same question arises that presents itself with 

 so many other Hawaiian plants, and that is, How has it happened 

 that the birds have continued to disperse the species over the 

 scattered islands of this group long after they ceased to transport 

 fresh seeds from the outside world ? The answer is an obvious one. 

 The birds that originally brought the seeds of the parent species 

 from some distant region came at last to remain permanently 

 in the Hawaiian Group, and not only the plant but probably also 

 the bird has since undergone specific differentiation. This link 

 between bird and plant in the floral history of a group of Pacific 

 islands is the common theme of the story of most of the endemic 

 species of plants in this region of the globe. 



GARDENIA (Rubiaceae). 



This genus, comprising about a hundred known species, is 

 spread over tropical Africa, Asia, and America, and over all the 

 groups of the tropical Pacific. On account of their handsome, 

 white, scented flowers these shrubs are much appreciated by the 

 Pacific islanders, who employ the flowers for personal decoration. 

 Some ten species have been described from the groups of the open 

 Pacific, all of which, with the exception of Gardenia tahitensis, 

 which ranges the South Pacific from Fiji to the Marquesas and 

 Tahiti, are seemingly peculiar to the different archipelagoes. 

 Thus there are some six species endemic to Fiji, one to Samoa, 

 and two to Hawaii. 



The Hawaiian Islands are, however, quite isolated in this 

 respect, since the group possesses only peculiar species ; whilst 

 a solitary species keeps up the connection between the groups on 

 the south side of the equator. The Gardenias thus tell the 

 same story of complete isolation in Hawaii, and of partial isolation 

 in the archipelagoes of the South Pacific that is repeated by many 

 other Pacific genera. Yet in Hawaii there has subsequently been 

 some inter-island dispersal, since the species are not restricted each 

 to a single island, but are found on two or three islands. The 



