71 



x li W^ &tl f m i -,-^,- 



Plate 26.— Classification: system Riverine, subsystem Tidal, CLASS Aquatic Bed, subclass Rooted Vascular, dominance type 

 Myriophyllum spicatum-Hydrilla verticillata-Heteranthera dvbia, WATER regime Permanently Flooded-Tidal, water CHEMISTRY 

 Fresh-Circumneutral. (Prince Georges County, Maryland; October 1985; Photo by V. Carter) 



