Shafer : Vascular Flora of Allegheny County. 117 



SYNTHERISMA Walter. 

 PANICUM Linnsus. 



* C. linearis (Krock). Small crab-grass. 

 P. glabrum Gaudin. 



* S. sanguinalis (Linnaeus). Large crab-grass. 

 P. sanguinale Linnaeus. 



PANICUM Linnceus. 

 -f- P. proliferum Lamarck. Spreading panicum. 



f P. capillare Linnaeus. Witch grass. 



f P. virgatum Linnaeus. Tall smooth panicum. 



f P. Porterianum Nash. Porter's panicum. 

 P. latifolium Walter. 



f P. clandestinum Linnsus. Hispid panicum. 



? P. commutatum Schultes. Variable panicum. 



f P, depauperatum Muhlenberg. Starved panicum. 



* P. pubescens Lamarck. Hairy panicum. 



f P. dichotomum Linnaeus. Forked panicum. 

 f P. laxiflorum Lamarck. Lax-flowered panicum. 



* P. Crus-galli Linnaeus. Cockspur grass. 



IXOPHORUS Schlechtendal. 

 SETARIA Beauvois. 



* I. verticillatus (Linnaeus). Foxtail -grass. 



