FOREIGN DRIFT OF THE TURKS ISLANDS 145 



ative capacity. It is thus evident that the tree possesses but little 

 fitness for effective trans-oceanic dispersal by currents; and it may 

 be inferred that if the fruits, in the shape of the " stones," ever 

 reached the shores of Europe, which is unlikely, they would either 

 be empty or would contain decaying seeds. 



But we may go further and observe that it is more than doubtful 

 whether the agency of the currents could be appealed to for an 

 explanation of the distribution of this tree over a large part of the 

 tropics of the New World. The reason of its representation in the 

 drift is probably to be found in its station on the forested slopes 

 of river valleys, from which the bared " stones " of the fruits could 

 be swept down into the rivers during torrential rains. If at times 

 they are carried by the sea currents in a sound state from one island 

 to another, the coast would offer a most unsuitable station for the 

 establishment of a typical tree of the inland forests. It is possible 

 that man has aided in its dispersal, since the edible fruit is appre- 

 ciated by natives; but the main factor is, I think, to be looked for 

 in the past, when the area of its distribution had not been broken 

 up in the great changes which have resulted in the detachment of 

 the large West Indian islands from the South American mainland, 

 a matter referred to on other pages of this work. 



In his account of the Cayman Islands, Mr. Savage English (Kew 

 Bulletin, 1913) tells us that the fruits of this tree are occasionally 

 thrown up on Grand Cayman "in a more or less eatable condition " ; 

 and he thinks that the tree may ultimately be introduced by the 

 currents. However, it is already included in the flora of the Cayman 

 Islands (Urban, Symbolce A?itillance, IV., 412) ; and if brought from 

 a distance the drift fruits in question doubtless came from the 

 neighbouring shores of Cuba and Jamaica. 



Gourds and Calabashes of the genus Crescentia 



In my work on Plant Dispersal (p. 570) it is observed that gourds 

 and calabashes of Cucurbitaceous plants are frequently brought 

 down to the sea in tropical regions and are thus likely to be dis- 

 persed by the currents. Floating in the estuaries and stranded 

 on the beaches, the gourds of a Cucurbita came often under my 

 notice in Fiji; and their suitability for dispersing the species was 

 established in one case, where seeds from a fruit that had been 

 floating for at least two months in sea-water germinated in a few 

 days. 



Gourds, usually small in size, were frequently observed by the 

 writer afloat in the drift of the estuary of the Guayas in Ecuador, 

 as well as stranded on the neighbouring beaches. Some of them 

 were cucurbitaceous; but others were the wild fruits of Crescentia 

 cujete, the Calabash tree, which belongs to quite a different family, 

 the Bignoniacece. It was not until some years afterwards that he 

 recognised these Crescentia fruits amongst his Ecuadorian drift- 

 collections, having in the interval become acquainted with the tree 

 in the West Indies. However, although the writer was not aware 

 of it, they had long before been identified as gourds of Crescentia 



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