The scattering of seeds along streams is too common a process to need more than a mere mention here, for it is to be seen along any fresh water stream at harvest time. But seeds that may be carried by ocean currents have a much greater influence on the distribution of plants, such as the coconut palm, already mentioned among the food plants, and now common throughout the tropical world. The number of seeds that will float in sea water and still keep the power of germinating is not very great. Most seeds sink at once; many will float for months, but are useless when they reach land; but those that will both float and grow afterward have worked some curious changes in the floras of different islands. Sometimes the great ocean currents, like the Gulf Stream, appear particularly futile in the fruits they carry such long distances, as the pods of a tropical vine from the West Indies are not infrequently found on the coast of Norway and even of Nova Zembla, of course uselessly. But many ocean currents, particularly in the Pacific, have carried fruits and seeds thousands of miles, they have even carried so-called floating islands of vegetation bodily. Perhaps the most remarkable case is that of _Entada scandens_, a tropical vine of the pea family, bearing large pods, sometimes several feet long. The plant is not typically a seaside plant, and there is evidence that fruits matured in the shade of its usual forest home will not float. Those that grow nearer the coast and more in the open develop, through partial drying, a small air chamber inside upon which the seed depends for buoyancy. Its original home is apparently somewhere in Central America, from the west coast of which it spread over the Pacific to the shores of the Indian Ocean. Over the Atlantic it has reached the shores of tropical Africa, and in fact wherever ocean currents cast up their refuse on lonely beaches parts of the giant pod or individual seeds of _Entada scandens_ are found. Partly fossilized remains of them have been taken from peat bogs along the coast of Norway, of course dating since glacial times, but showing by their presence there how long this water-borne seed of the pea family has been attempting to populate the earth. Of course all that do not reach tropic shores are lost, but nearly throughout the Pacific Islands, with some exceptions, the vine is now established. The extraordinary feature of it all is that scarcely half the seeds of the plant will float at all, nearly all inland forms sinking at once in the fresh water rivers into which they may chance to fall. Only those that grow near the sea, in mangrove swamps and the like, or at any rate near brackish water, will float. These, however, apparently float indefinitely without loss of germinating power. There is abundant evidence that many plants of oceanic islands have similar characteristics so far as their inland and seaside forms are concerned.