414 THE PLANT LIFE OE MARYLAND 



Xyris caroliniana Walt. 



Coastal and Midland Zones; in marshes, swamps and open wet situa- 

 tions; frequent. 

 Worcester County, Snow Hill (1043) ; Wicomico County, Shad Point 

 (1201).* 



ERIOCAULACEAE. 



Eriocaulon septangulare With. Pipewort. 



Common in the Coastal Zone, infrequent in the Midland, being most 



abundant in the shallow water and fresh estuaries about the head 



of the Chesapeake Bay. 

 Cecil County, Furnace Creek (402). 



Eriocaulon decangulare L. 



Confined to the Coastal Zone; in fresh marshes and bogs; infrequent. 

 Wicomico County, near Vienna (1300). 



COMMELINACEAE. 



Commelina nudiflora L. Day-flower. 



Throughout the state; in moist cultivated grounds; common. 



Commelina hirtella Vahl. 



Confined to the Coastal Zone; in swamps and moist forests; rare. 

 Worcester County, Steves Island (669). 



Tradescantia virginiana L. Spiderwort. 



Throughout the state; in moist waste grounds; common. 



PONTEDERIACEAE. 



Pontederia cordata L. Pickerel-weed. 



Throughout the state; in marshes and swamps and about the edges of 

 ponds; common in the Coastal Zone, less frequent in the Midland and 

 Mountain Zones. 



Heteranthera reniformis R. & P. 



Costal and Midland Zones; in shallow water, about the edges of ponds 



and in the estuaries at the head of the Chesapeake Bay. 

 Cecil County, Furnace Creek (399). 



Heteranthera dubia (Jacq.) MacM. Water Star-grass. 



Washington County, near Hancock (790). 



*This number was determined by the United States National Herbarium as Xyria 

 flmbriata Ell. 



