XIV LITTORAL AND INLAND PLANTS' RELATIONSHIP 135 



number of genera here concerned. We will first deal with the 

 genera Calophyllum, Morinda, and Scaevola, where the littoral 

 species have buoyant fruits or seeds that are dispersed by currents, 

 whilst the inland species have more or less non-buoyant fleshy 

 fruits that could only be dispersed by frugivorous birds. Here the 

 inland and coast species could have arrived independently at the 

 island, and we are not called upon either on this ground or by 

 reason of affinity of characters to connect the one with the 

 other. 



The genus Scaevola is very typical of its kind and has been 

 already in part discussed in Chapter II. The wide-ranging shore- 

 species, S. Koenigii, that is distributed over the Pacific may some- 

 times, as in Hawaii, be accompanied by numerous inland species, 

 all endemic, seven of them being enumerated by Hillebrand ; or, 

 as in Fiji and Tonga, there may be associated with it a solitary 

 inland species, S. floribunda (see Note 51) ; or, as in Tahiti, it may 

 exist by itself. On the other hand, as in the Kermadec Islands, 

 a single inland peculiar species may alone represent the genus. 

 The inland species have fleshy drupes which, as far as examined, 

 have no floating power and possess no buoyant tissues in their 

 coverings ; and their independent dispersal by birds cannot be 

 doubted. The endemic character of most of the inland species of 

 the Pacific islands is most probably due to the suspension of the 

 transporting agency of frugivorous birds, just as the wide range 

 of the solitary littoral species may be attributed to the uninter- 

 rupted agency of the currents. There is nothing in the description 

 of the endemic species given in Hillebrand's Hawaiian Flora 

 to indicate any especial genetic connection between the inland 

 species and the beach plant, S. Kcenigii; and the occurrence of 

 a solitary inland peculiar species in the Kermadec Islands clearly 

 proves an origin independent of any littoral plant. 



Morinda is another critical genus in this discussion. Besides 

 the widespread littoral species (M. citrifolia) that is distributed by 

 the currents and is also dispersed by man, there are in the Pacific 

 islands a number of inland species, mostly climbers and denizens of 

 the forests. In the Index Kewensis six are accredited to Fiji and five 

 to New Caledonia. Hillebrand gives a peculiar Hawaiian species, 

 and there is a widespread species (M. Forsteri) that ranges over 

 the South Pacific from New Caledonia to the Marquesas and the 

 Paumotu Islands. Since, as indicated in Chapter II. and in Note 8, 

 the pyrenes of the fruits of the inland species are not dispersed by 

 the currents and could readily be transported by frugivorous birds. 



