Peltandra ARACEAE— LEMNACEAE Wolffia 



Peltandra Raf. Arrow Arum. 

 ff P. virginica (L.) Kunth. See Fernald : Rhodora 42, 430-432. 1940. 



. \ • Frequent on the Coastal Plain, in marshes, shallow water and 

 L J^^ tidal mud. No specimens seen from south of the Virginia line. 

 June, mid-July. 



Symplocarpus Salisb. 



S. foetidus (L.) Nutt. Skunk Cabbage. 



Common in wet places, at least north of the Virginia line. 

 March, April. 



Orontium L. 



O. aquaticum L. Golden Club. 



Frequent; swamps and margins of streams on the Coastal 

 Plain. April, May. 



Acorus L. 



U II A. Calamus L. Sweet Flag. 



Common in low ground, especially on the Coastal Plain north of 

 the Virginia line. May, June. v^ ^ 



LEMNACEAE (Duckweed Family) 

 Spirodela Schleiden. Duckweed. 



S. pol3rrhiza (L.) Schleid. 



Common, floating on fresh-water ponds and slow streams, often 

 densely covering the surface. 



Lemna L. Duckmeat. 

 L. minor L. 



In the same habitats as Spirodela, and often accompanying it. 

 Both are very common in our area, in both Piedmont and Coastal 

 Plain provinces. 



L. perpusilla Torr. 



Rare, in ditches about Wilmington: Canby in 1872, 1893 and 

 1899 (D). 



Wolflla Horkel. 

 W. Columbiana Karst. 



Found floating in great abundance in a few ponds and canal 

 coves in New Castle County: Chesapeake & Delaware Canal, near 

 Delaware City, Commons & Talnall, Sept. 1896 (A, D) ; pool along 



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