xxvi ELAEOCARPUS 



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in the Admiralty Islands were those of Elaeocarpus ; whilst in the 

 Solomon Islands I noticed that the blue fruits of the " Toa," a 

 species of the genus, were a favourite food of the same birds (Bot. 

 Chall. Exped., iv. 307, 308 ; Guppy's Solomon Islands, 293, 295). 

 We learn also from Hochstetter and from Sir W. Buller that the 

 drupes of the " Hinau " (Elaeocarpus) form a favourite food of 

 the parrots and fruit-pigeons of New Zealand (Hochstetter's New 

 Zealand ; Buller's Birds of New Zealand). 



The question of size acquires considerable importance when we 

 come to consider the transport of the seeds of the genus to a 

 group of islands lying, like Hawaii, in the middle of the Pacific 

 Ocean. The protection of the seed is also another important 

 matter. There can, however, be no doubt that the hard woody or 

 often osseous " stone " sufficiently protects the seed. With regard 

 to size, if we were to judge from the dimensions of the fruits of 

 some of the Fijian species, where, as I found, the " stone " measures 

 from 3 to 5 centimetres {\\ to 2 inches) in length, we might be led 

 to form a very erroneous opinion of the capacity of the genus for 

 conveyance through the agency of frugivorous birds to Hawaii. 

 But when we turn to the Hawaiian species we find the difficulty 

 much diminished, though still serious, the fruits being smaller and 

 possessing a "stone" 2% centimetres or about an inch long. In 

 other regions, however, the genus may possess fruits yet smaller in 

 size. The Tongan endemic species, as described by Burkill, has 

 fruits 17 cm. or T 7 <j- of an inch in length ; and closely similar 

 dimensions are given by Kirk for a New Zealand species. In both 

 these cases the " stone " would not be more than half an inch or 

 I "2 cm. in length, and this would also apply to the Solomon Island 

 species above mentioned. In another New Zealand species, where 

 the drupe is only half an inch, the " stone " would be still smaller. 

 It is thus evident that the fruits of different species vary greatly in 

 size in different regions, and that there is no difficulty in assuming 

 that a small-fruited species could be dispersed over the Pacific 

 by frugivorous birds, and carried either to Hawaii or New 

 Zealand. 



It might be an interesting point to determine to what extent 

 a species in an oceanic island could effect its own isolation by 

 developing a " stone " too large and too heavy to be transported 

 across an ocean by birds, such as seems to have happened with 

 some Fijian species. But a similar curious question is raised 

 by the deterioration of a drupe in its capacity for dispersal by 

 frugivorous birds, when, as in the case of the Hawaiian species 

 VOL. 11. z 



