FLOATING POLLEN 



In Britain we have the "sea meadows" of Sea-grass, 

 which covers the submerged sand and mudbanks near the 

 mouths of great rivers. 



The waving green grasslike leaves form a rich submarine 

 meadow. They are used for stuffing pillows and cushions, 

 especially in Venice, but their real importance in the world 

 depends upon their being able to tie down and fix per- 

 manently those unseen shifting banks which form a real 

 danger to all navigation. 



These plants are very remarkable. They lived, no doubt, 

 at one time on the land, like most of the flowering plants. 

 But, like the whale and the seal, they have been driven 

 to take refuge below the ocean. They are not easily seen, 

 and, indeed, one may wander for years along the sea-coast 

 and never suspect that great meadows of Zostera (the 

 Eelwrack, Grasswrack, or Sea-grass) are flourishing under 

 water. 



But, one might ask, how is the pollen of its flowers 

 carried ? Obviously neither insects nor the wind can be 

 of any service. The pollen of Zostera is, however, of the 

 same weight exactly as the water, so that it neither rises 

 to the surface nor sinks to the bottom, but floats to and 

 fro until it reaches the outspread styles of another plant. 

 This is perhaps the most remarkable arrangement known for 

 the carrying of pollen. 



Sometimes along the seashore, or especially on the muddy 

 foreshore of an estuary or tidal river, one can watch those 

 plants which are trying to form new land. One finds 

 generally that there is a broad stretch of marshy meadow 

 interrupted and intersected by small ditches and little 

 winding streams. As one gets towards the shore. Sea-pink, 

 Scurvy-grass, an Aster, and other plants, not to be found 



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