Il6 POACEAE 



Tertiary, common: Cretaceous, common: Older Formations: 

 known only on the "River Mud," underlying Tinicum, Delaware 

 Co., Pa., in our area. 159-220 days. About sea level. 



56. P. scabriusculum Ell. In swampy places and ponds: N. J. 



to W. Va., Fla. and Tex. 



N. J. At Hospitality Bridge, Folsom, Pleasant Mills and north 

 of Atsion in the pine-barrens and at Atlantic City (according to 

 Hitchcock & Chase). A rare and apparently northward migrat- 

 ing species. 



57. P. cryptanthum Ashe. In dry or moist soil: N. J. to Fla. and 



Tex. 



N. J. From Atlantic City southward along the coast, and at 

 Folsom in the pine-barrens; very rare. 



58. P. aculeatum Hitchc. & Chase. In open sandy places: N. Y. 



to D. C. and N. Car. 



N. Y. Rockville Centre and Hempstead, L. I., on or near the 



Hempstead Plains. 

 N. J. Reported from Cape May, and Albion, Camden Co.; rare. 



59. P. Ashei Pearson. In dry woods: Mass. to Mich., south to 



Fla., Miss, and Mo. 



Throughout the range, less common in the north, increasing 

 southward. 



60. P. commutatum Schult. In dry woods and thickets: Mass. to 



Mo., Fla. and Tex. 



N. Y. Rare on S. I., and at the New York Botanical Garden, not 



recorded elsewhere in our area. 

 N. J. Rare at Rosemont, Hunterdon Co., and at Bennett, Cape 



May. 

 Pa. Recorded from Northampton, Bucks, and Delaware counties. 



61. P. latifolium L. (P. macrocarpon Le Conte). In woods: Me. 



to Minn., south to N. Car. and Kan. 



Conn. Throughout. 



N. Y. Common on L. I. (according to Bicknell) ; and S. I., in West- 

 chester Co., thence increasing northward. 



N. J. Rare in Gloucester Co., near the Delaware, not recorded 

 thence to Essex Co., thence increasing northward. 



Pa. Chester, Philadelphia, Bucks, Northampton, Monroe and 

 Luzerne counties. 



