XXIX BEACH AND RIVER-DRIFT ' 439 



(3) Time has gathered on an English beach current-dispersed 

 plants that could tell us strange stories of many latitudes. 



(4) The seed-drift that is often found in such abundance in 

 tropical seas is partly brought down by rivers and partly swept off 

 the coast. Very little- of the seed-drift brought down by the rivers 

 from the interior is of any service for plant-dispersal, nearly all the 

 floating seed-drift found at sea which has any effective value being 

 derived from the plants of the beach and of the mangrove belt. 



(5) The tropical beach drift of the Old and New Worlds reflects 

 the characters of the littoral floras of those regions, more especially 

 with regard to the plants provided with buoyant seeds or seed- 

 vessels. The plants represented in the beach drift common to both 

 these regions belong mostly to the Leguminosae. The large fruits 

 so characteristic of Old World beach-drift are not found in the 

 New World. The number of shore plants with buoyant seeds or 

 seed-vessels that are widely dispersed in the American region are 

 only one-quarter or one-third of those in the Old World region ; 

 and this difference is reflected in the scanty character of tropical 

 American beach-drift. 



