POACEAE. 17 



ones 4-8 cm. long, usually 4-8 mm. wide, rarely wider, those on the branches 

 much smaller, often involute: panicle 4-8 cm. long, broadly ovate: spikelets 

 rather few, 1.75-2 mm. long and 0.8-1 mm. wide, elliptic, glabrous. Common, 

 on roadsides and in thickets. Sum. 



14. P. microcarpon Muhl. Glabrous. Stems densely tufted, at first erect, 

 finally much branched and decumbent, the nodes strongly barbed with silky some- 

 what reflexed hairs: primary leaf -blades spreading, sometimes somewhat re- 

 flexed, usually 6-10 cm. long, 8^15 mm. wide, lanceolate, the blades on the 

 branches much smaller: panicle finally much exserted, 711 cm. long, oval: 

 spikelets 1.5-1.8 mm. long and about 0.8 mm. broad, elliptic, glabrous. [P. 

 nitidum var. barbulatum (Michx.) Wood.] Eather common, in moist grounds 

 and thickets. Sum. 



15. P. Lindheimeri Nash. Stems tufted, 4-8 dm. tall, glabrous, finally much 

 branched: leaf -blades erect, glabrous, or the lower surface sometimes minutely 

 pubescent with short hairs, ciliate at 'the base, the primary ones 2-8 cm. long, 

 3-8 mm. wide, lanceolate, firm, the blades on the branches much smaller : panicle 

 3-8 cm. long, broadly ovoid: spikelets about 1.5 mm. long and 0.8 mm. wide, 

 obovoid. S. Frequent, on dry sandy banks. Schists. Sum. 



16. P. Huachucae Ashe. Stems at first erect and simple, later profusely 

 branched and leaning or ascending, glabrous or pubescent: leaf -sheaths hirsute, 

 often papillose; blades hirsute, especially beneath, erect or spreading, those on 

 the main stem 5-8 cm. long, those on the branches much shorter: primary 

 panicle less than 8 cm. long, ovoid : spikelets hardly 2 mm. long. [P. pubescens 

 A. Gray, not Lam.] Common, in dry soil. Sum. 



17. P. tennesseense Ashe. Stems tufted, 4-6 dm. tall, rather weak and ascend- 

 ing, papillose-hirsute with long spreading hairs, finally much branched and 

 prostrate: leaf -sheaths densely papillose-hirsute with long spreading hairs; 

 blades ascending, lanceolate, the upper surface with scattered hairs, the primary 

 blades 4-10 cm. long, 5-10 mm. wide, those on the branches much shorter and 

 spreading with the upper surface nearly glabrous: panicle 7-10 cm. long, ovoid, 

 its branches ascending: spikelets 1.7-2 mm. long, 0.8^0.9 mm. wide, elliptic or 

 obovoid. M. S. Eather rare, in dry soil. Limestones, schists. Sum. 



18. P. Scribnerianum Nash. Stems tufted, erect, 1.5-6 dm. tall, simple, finally 

 dichotomously branched above: leaf -sheaths strongly papillose-hispid; blades 

 5-10 cm. long, 6-12 mm. wide, spreading, glabrous: primary panicle ovoid, 

 4-8 cm. long: spikelets turgid, obovoid, about 3 mm. long, glabrous, or some- 

 times pubescent with short spreading hairs. S. Eather rare, in dry thickets. 

 Schists. Sum. and fall. 



19. P. sphaerocarpon Ell. Stems generally erect, simple or somewhat branched 

 at the base, 2.5-6 dm. tall: leaf -blades 5-10 cm. long, 4-14 mm. wide, rough 

 above, smooth beneath, the margins cartilaginous and minutely serrulate, ciliate 

 toward the base: panicle ovoid, 5-10 cm. long: spikelets less than 2 mm. long, 

 nearly spherical, or a little longer than thick, obtuse. M. S. Eather rare, 

 in dry woods and thickets. Limestones, schists. Sum. 



20. P. polyanthes Schult. Stems generally erect, 6-9 dm. tall, simple, gla- 

 brous: leaf -blades 1-2 dm. long, 1-2.5 cm. wide, long-acuminate, smooth, cor- 

 date-clasping and sparingly ciliate at the base : panicle 7-20 cm. long, ovoid to 

 oblong: spikelets 1.5 mm. long, obovoid to nearly spherical, numerous, puberu- 

 lent. Common, along the Susquehanna. In dry thickets or woods. Lime- 

 stones, schists. Sum. 



21. P. commutatum E. & S. Stems tufted, glabrous, erect, 3-6 dm. tall, finally 

 rather sparingly branched : leaf -blades ciliate on the margin, otherwise glabrous, 

 cordate and clasping at the base, those on the stem larger than the basal ones, 

 5-12 cm. long, 1-2 cm. wide, ovate-lanceolate: panicle 5-10 cm. long, broadly 

 ovoid: spikelets 2.5-3 mm. long and about 1 mm. wide, elliptic, obtuse or acutish, 



Lancaster County Flora 2. 



