DIFFICULTIES OF MARITIME DISTRIBUTION. 277 



waves. It is only where the shore is being undermined or through 

 some other relatively infrequent accident that the nuts would fall into 

 the water. It is true that accounts of floating cocoanuts are to be 

 found in Dampier's Voyages and elsewhere, but such records show the 

 rarity rather than the frequency of the occurrence and give us, in 

 addition, no evidence on the viability of the seed observed. The addi- 

 tional facts may be cited on that side that the Hindoos have a festival 

 in which it is customary to throw large numbers of cocoanuts into the 

 sea, while many must be swept away from the coasts of continents and 

 large islands by floods and swollen rivers. But it is far from correct 

 to suppose that all nuts which reach the water are really launched for 

 oceanic wanderings; the chances are still hundreds to one that they 

 will be thrown back immediately upon their own coast, like other 

 objects floating in the surf. High waves or tides, instead of floating 

 shore debris away, merety carry it farther inland, as everybody famil- 

 iar with seacoasts knows. 



Then from the nuts which might reach the open sea take all except 

 the infinitesimal number which would arrive anywhere while still 

 alive, and reduce this by an 'equally great proportion which would 

 simply be cast up to dry on the sand; reduce again for those which 

 would be thrown back and smothered in the bushes or find unsuitable 

 conditions of growth, and you have left still a possibility, it is true, 

 but of a very high order of infinitesimals and utterlj- inadequate to 

 accomplish the widespread distribution of the present species. Empty 

 husks must not be counted; these sit high in the water and might 

 easily be floated or blown off shore and would make quick journeys. 1 



In Island Life, Wallace refers to the double cocoanut {Lodoicea 

 maldivica) as furnishing a conspicuous instance of maritime distribu- 

 tion. In reality, however, this case proves just the contrary of what 

 was intended; for, although double cocoanuts have been thrown up for 

 centuries on the shores of the Maldive Islands and of other parts of 

 the East -Indies, this transfer of nuts seems never to have resulted in 

 the establishment of a single tree of Lodoicea outside the three small 

 islands to which it is confined in the Sej^chelles. Until the explora- 

 tions of Europeans resulted in the discovery of the palms, the East 

 Indians had universally believed that the nuts were a marine product, 

 on which they placed the highest value because of supposed medicinal 

 qualities. 



Shipwrecks would undoubtedly furnish the most successful method 

 of launching viable cocoanuts, and if, as has more than once happened 



Experiments like those of Guppy (Journ. Trans. Victoria Inst. , vol. 24, p. 305, 

 1891) on the periods of flotation of seeds are of value, of course, only when it can be 

 shown that the dry seeds will germinate after floating for long periods in salt water. 

 The drier the seeds to begin with, the better they will float, but many tropical 

 species are like the cocoanut in that their seeds when dry are dead. 



