This section is from the book "Harper's Guide To Wild Flowers", by Caroline A. Creevey. Also available from Amazon: Harper's Guide To Wild Flowers.
Color, light brown. In this species the staminate and pistillate flowers are usually separated by a space of 2 or 3 inches. Leaves, quite long and narrow.
Not so common as the preceding, and mostly found in shallow water near the coast.
 
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