CYPERACEAE 155 



11. C. dentatus Torr. In sandy swamps and on shores: Me. to 



northern N. Y., W. Va. and S. Car. 



Conn. Throughout, but not common. 



N. Y. Rare on L. I. as at Yaphank and Ronkonkoma, recorded 

 from but not definitely known on S. I., thence scattered up the 

 Hudson Valley to Columbia Co. ; not known from the Catskills. 



N. J. Bergen, Essex and Warren counties, increasing southward. 



Pa. Northampton and Bucks counties. 



12. C. rotundus L. In fields: Va. to Fla., Mo., Kan. and Tex. 



Adventive in ballast near the eastern seaports. 



Rare as a ballast weed near Philadelphia and Bethlehem, Pa. 



13. C. esculentus L. In moist fields: N. B. to Minn., Neb., Fla. 



and Tex. Also on the Pacific Coast, Trop. Am. and the Old 

 World. 



Common throughout the range in some of its forms, but appar- 

 ently only adventive and rare in the pine-barrens. 



14. C. erythrorhizos Muhl. In wet soil: southern Ont. to Mass., 



Fla., Minn., Kan., Tex. and Cal. 



Throughout the range except in the pine-barrens and on S. I.; 

 and not definitely known from the Catskills. 



15. C. speciosus Vahl. In marshes: Mass. to Ohio and S. Dak., 



south to Fla., Kan., Tex. and Cal. 



Conn. Rare along the coast, decreasing and perhaps wanting, 



inland. 

 N. Y. Rare in Westchester Co., increasing southward. 

 N. J. Rare in Bergen and Hudson Co., increasing southward, 



but not in the pine-barrens. 

 Pa. Northampton, Schuylkill, Bucks, Philadelphia, Delaware and 



Chester counties. 



Tertiary, not on Beacon Hill, common elsewhere: Cretaceous, 

 common: Older Formations, rare, more common near the coast 

 than elsewhere. 169-220 days. About sea-level. 



16. C. ferax L. C. Rich. In wet soil: Mass. to Fla., Cal. and in 



Trop. Am. 



Known definitely only from near Secaucus, N. J. 



17. C. Engelmanni Steud. In wet soil: Mass. to S. Ont. and 



Wise, south to N. J. and Mo. 



