1918] The Grasses of Illinois 311 



to 1.9 mm. long, densely pubescent. Autumnal form much branched 

 at the nodes, the branches closely appressed to the stem; leaves only 

 slightly smaller than in the spring form, and partially concealing the 

 much reduced panicles. 



This species is found on dry prairie and in clearings. It has been 

 found only in the middle western states. The type locality for the 

 species is Wady Petra in Stark county. 



ILLINOIS SPECIMENS : Without locality, Vasey. champaign co. Champaign, 

 Waite, June, 1886; Urbana, Seymour, May, 1880. jo daviess co. Hanover, Glea- 

 son and Gates, June, 1908 ; without locality, Pepoon .02 and .04. knox co. Wil- 

 liamsfield, F. H. Chase 1850. lake co. Winthrop Harbor, Gates 2778;'Waukegan, 

 Gates 2469. la salle co. Starved Eock, A. Chase 1605. Marshall CO. With- 

 out locality, V. H. Chase, 1791. mason co. Havana, Gleason 1034. stark co. 

 Wady Petra, F. 11. Chase 472, 649, 1212, 1214, 1218. will co. Joliet, Hill in 

 1907. 



Panicum pseudopubescens Nash 

 (Fig. 78) 



Panieum sp., Gleason '07, 181. P. pseudopubescens, Gleason '10, 147; Hitch- 

 cock and Chase '10, 235. 



Vernal form with stiff culms 8 to 20 inches tall ; culms and sheaths 

 densely pubescent, the hairs usually as long as the width of the culm ; 

 nodes densely bearded with spreading hairs ; sheaths shorter than the 

 internodes; ligule about 2 to 3 mm. long; blades 2 to 4 inches long, 5 

 to 10 mm. wide, the upper surface long pubescent near the edge, smooth 

 in the center, occasionally smooth all over, the lower surface with 

 short, fine pubescence ; spikelets 2.2 to 2.4 mm. long, densely pubescent. 

 Autumnal form usually with spreading culms, sometimes flat on the 

 ground, with a few branches at each node ; leaf blades considerably 

 reduced and usually smooth. 



This species is usually light olive green in color. It is found in 

 sandy soil, often in open woods. Gleason found it very abundant in 

 the sand areas which he studied. There it formed one of the charac- 

 teristic bunch grasses where the sand was being continually blown 

 away from the roots of the -plants. 



JO DAVIESS CO. Hanover, Gleason and Gates 2535, 2539, 2575. LA salle co. 

 Starved Eock, A. Chase 1605; Starved Eock, STceels, May, 1905. 



Panicum tennesseense Ashe 

 (Fig. 79) 



Hitchcock and Chase '10, 218. 



Vernal form 10 to 25 inches tall, stiffly erect or slightly spread- 

 ing; culms and sheaths with short hairs, sometimes nearly smooth; 

 ligules 4 to 5 mm. long ; nodes bearded ; sheaths shorter than the inter- 

 nodes ; blades 2 to 3.5 inches long, 5 to 8 mm. wide, with a very narrow 

 white margin, upper surface with a few long hairs near the base, the 



