i62 A NATURALIST IN THE PACIFIC chap. 



Section V. 



In this section are included those genera where within the same 

 genus some inland species have been derived from the coast species 

 whilst others have been originally brought by birds. Guettarda alone 

 belongs here. In this genus we find, as is so frequently the case, 

 a littoral tree (G. speciosa) widely spread in the Old World and 

 ranging over the whole tropical Pacific as far east as Pitcairn and 

 Elizabeth islands, but absent from Hawaii. Here also as with 

 Pandanus it is only in the Western Pacific that we find inland 

 endemic species so distinct in character from the littoral tree that 

 they may be regarded as of independent origin. 



Since, however, there is an inland form of the coast species in 

 Tahiti (Guettarda speciosa, var. tahitensis) which, according to 

 Drake del Castillo, is distinguished only by its more rounded 

 leaves and by the more marked pubescence of the under leaf- 

 surfaces, we evidently have there an inland species in process of 

 development from the littoral species. This inland tree is found 

 at elevations as great as 600 metres or almost 2,000 feet above the 

 sea ; and indeed if we follow Nadeaud the specific differentiation 

 is complete. However, there is no doubt raised as to its close 

 affinity to the beach tree ; and we are almost compelled for another 

 reason to regard it as a derivative of the shore species, because, as 

 pointed out in Chapter XXVIL, there are very few inland plants in 

 the Tahitian flora possessing fruits as large as those of Guettarda 

 that owe their presence in those islands to frugivorous birds. 



Of the two inland species of the genus found in Fiji, G. 

 inconspicua and G. vitiensis, it may at once be said that, as indicated 

 in Dr. Seemann's work, their characters are far from suggesting any 

 connection in origin with G. speciosa, the shore-species, the inland 

 and littoral plants belonging to different sections of the genus. In 

 their case we can only look to the frugivorous bird for the explana- 

 tion of their existence in the group. The fruits would be probably 

 small ; and in this connection it is to be noted that Mr. H. N. 

 Ridley in his paper on the flora of Fernando Noronha evidently 

 looks to birds to account for the presence of a species of Guettarda 

 on the island, a species not found elsewhere. 



But another inland Fijian form of Guettarda found by me in 

 Vanua Levu at elevations of 1,000 to 1,400 feet above the sea, and 

 dubbed by the natives with the name of the littoral tree (Mbua- 

 mbua), corresponds in its close relation to G. speciosa with the 



