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, 7-11 cm. long, oval: 

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

 nitidum var. harhulatum (Michx.) Wood.] — Rather common, in moist grounds 

 and thickets. — Sum. 



15. P. Lindlieimeri 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-S 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. 

 — ScJiists. — 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. 



