Fortunate Islands 
light seeds which could be easily carried by the wind, 
and this is found to be actually the case. 
One might suppose also that those trees which have 
aeroplane seeds or fruits would also be found on them, 
but this has been questioned. One of the neatest con- 
trivances of this kind is found in Shorea, a tree of the 
Malayan peninsula. According to Mr. Ridley, however, 
the fruit cannot fly for more than forty yards. As the 
tree cannot produce fruits until it is at least thirty years 
old, he calculates that it would take 58,666 years to 
travel a hundred miles, and must have required about 
1,500,000 years to get to the Philippines from its present 
home in Malaya. 
One feels a little doubtful as to whether a hurricane 
or typhoon might not be trusted to do better than 
merely carry a winged fruit for forty yards, but the pro- 
portion of aeroplane fruits and seeds in island floras is 
not large. Birds, however, assist in carrying fleshy, 
sticky, and spiny fruits from island to island, and 
especially those which have hard and indigestible seeds. 
They have wonderful capacities in the way of swallowing, 
as can be seen even in Britain by watching a wood- 
pigeon when dealing with an acorn, and the beautiful 
South Sea pigeons have probably been of great help in 
supplying islands with new plants. Migrating birds are 
sdid to travel enormous distances. 
A curlew may possibly leave a Scotch moor and 
eventually arrive at Kimberley in South Africa The 
little arctic bluethroat is said to go from Heligoland to 
Morocco in a single flight without resting anywhere ex 
route. Surely, however, the bird would take the simple, 
obvious precaution of clearing its plumage of all mud 
and sticky or spiny fruits before starting on a voyage 
of this kind ? 
But it is the navigator plants of the South Seas that 
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