vi THE TAHITIAN STRAND-FLORA 49 



other parts of the South Pacific. Thus we find here on the sandy- 

 beaches Barringtonia speciosa, Calophyllum Inophyllum, Cerbera 

 Odollam, Hernandia peltata, Guettarda speciosa, and numerous other 

 plants that are indicated by the letter T in the list of Fijian littoral 

 plants given in Note 2. The total number of Tahitian shore-plants 

 is thus considerably less than that of Fiji (there are about 55 in 

 Tahiti and about 80 in Fiji) ; but in its turn, as will subsequently 

 be shown, it is much larger than that of Hawaii, where the number 

 is about 30. 



Quite three-fourths of the strand-flora of this region have 

 buoyant seeds or seedvessels capable of floating for long periods ; 

 and there is no difficulty in assigning by far the greater share in 

 the stocking of the beaches with their plants to the agency of the 

 currents. The currents in their operations have indeed carried the 

 fruits or seeds of many of these plants across the South Pacific as 

 far as the islands extend, namely, to Ducie Island and to Easter 

 Island. There are few more significant proofs of the efficacy of the 

 currents in distributing plants over the Pacific than the discovery, 

 by Mr. Arundel, of Barringtonia speciosa in Ducie Island in 

 association with Tournefortia argentea (Challenger, Botany, 

 III. 116). 



The residue of the Tahitian coast flora possessing fruits or seeds 

 that are unsuited for dispersal by currents includes such plants as 

 Heliotropium anomalum, Triumfetta procumbens, Tephrosia pisca- 

 toria, Wikstroemia fcetida, &c. The small nucules of the first-named 

 are perhaps dispersed by granivorous birds ; the fruits of Triumfetta 

 are probably transported in birds' plumage ; those of Wikstroemia 

 are distributed by frugivorous birds ; and the seeds of Tephrosia 

 may be dispersed like those of Heliotropium. 



The recruits or intruders from the inland flora do not appear to 

 be numerous or to give any special character to the shore flora. 

 (See Note 27.) 



From not having a personal acquaintance with this region it is 

 not possible for me to discuss the extension of the shore-plants 

 inland except in a general way. From the pages of the work of 

 Drake del Castillo we can, however, infer that several plants such as 

 Cassytha filiformis, Cerbera Odollam, Colubrina asiatica, Hernandia 

 peltata, Morinda citrifolia, and Pandanus odoratissimus have 

 extended inland to the mouths of the Tahitian valleys, and have 

 ascended the lower slopes of the hills that lie near the coast. 

 Others, like Csesalpinia Bonduc, Gyrocarpus Jacquini, and Ochrosia 

 parviflora, have climbed far up the mountain-sides to elevations of 



VOL. 11 E 



