Aquatic Seed Plants 



157 



families are best represented whose members live 

 chiefly on low grounds and in moist soil. A few rushes 

 (Juncacese) invade the water on wave-washed shores 

 at fore front of the standing aquatics. A few sedges 



Fig. 67. Fruit clusters of four emergent aquatic seed 

 plants; arrow-arum {Peltandra), pickerel- weed {Pon- 

 tfderia), burr-reed (Sparganium) , and sweet flag 

 (Acorus). 



(Carices) overrun flood-plains or fringe the borders of 

 ditches. A very few grasses preempt the beds of 

 shallow and impermanent pools. A few aroids, such 

 as arrow arum and the calla adorn the boggy shores. 

 A few heaths, such as, Cassandra and Andromeda over- 

 spread the surface of upland sphagnum bogs with dense 



