16 POACEAE. 



1. P. capillare L. Stems 3-6 dm. tall, simple, or branched near the base, stout: 

 leaf-sheaths usually purplish, papillose-hirsute; blades 1.5-8 dm. long, 6-16 mm. 

 wide, pubescent: primary panicle 2-3.5 dm. long, the lateral panicles smaller: 

 sptkelets very numerous, 2-2.5 mm. long, lanceolate, acuminate. — Common, in 

 waste grounds and cultivated soil. — Sum. and fall. 



2. P. philadelphicum Bernh. Stems erect, 2-6 dm. tall, slender, somewhat 

 branched at the base : leaf -sheaths hirsute ; blades 5-10 cm. long, 2-6 mm. wide, 

 erect, pubescent: panicle 10-23 cm. long: spikelets about 1.5 mm. long, elliptic, 

 acute. — S. Eather rare, borders of woodland. — Schists. — Sum. and fall. 



3. P. flexile (Gattinger) Scribn. Stems erect, 1.5-4.5 dm. tall, slender: leaf- 

 sheaths papillose-hirsute; blades 10-23 cm. long, 4-6 mm. wide, erect, long- 

 acuminate, pubescent: panicle 1-2.5 dm. long: spikelets about 3 mm. long, 

 acuminate. — M. Bare, in moist soil, Dillerville swamp. — Limestones. — Sum. 

 and fall. 



4. P. millaceum L. Stems erect or decumbent, 3 dm. tall or more: leaf -sheaths 

 papillose-hirsute; blades 1-2.5 dm. long, 8-25 mm. wide, pubescent: panicle 

 rather dense, 1-2.5 dm. long: spikelets 5 mm. long, acuminate. — M. Eather 

 rare, in waste or cultivated grounds. Nat. of Eu. — Sum. and fall. — Millet. 



5. P. dichotomiflorum Michx. Stems at first erect, 3-6 dm. tall, simple, later 

 decumbent, 1-1.5 m. long, branched at all the upper nodes: leaf -sheaths loose, 

 glabrous, somewhat flattened; blades 1.5-6 dm. long, 4-20 mm. wide: panicle 

 pyramidal, 1-4 dm. long: spikelets 2-3 mm. long, lanceolate, acute. — Common, 

 on roadsides and in moist soil. — Sum. and fall. 



6. P. virgatum L. Glabrous. Stems erect, 9-15 dm. tall: leaf -blades elon- 

 gate, 3 dm. long or more, 6-12 mm. wide, flat: panicle 1.5-5 dm. long: spike- 

 lets ovate, acuminate, 4-4.5 mm. long. — Common, in moist pastures, and on 

 roadsides and river banks. — Sum. and fall. 



7. P. agrostoides Muhl. Stems 4-8 dm. tall, much branched, compressed: leaf- 

 blades 3 dm. long or more, 4-8 mm. wide: panicle pyramidal, 1-3 dm. long, its 

 branches spreading: spikelets 1.5-2 mm. long, acute, straight. — -Frequent, in 

 moist grounds. — Sum. and fall. 



8. P. longifolium Torr. Stems 3-6.5 dm. tall, slender, usually simple: leaf- 

 blades 2-3 dm. long, 2-4 mm. wide: panicle 1-2.5 dm. long: spikelets 2 mm. 

 long, acuminate. — S. Eare, in swamps. — Schists. — Sum. and fall. 



9. P. stipitatum Nash. Stems erect, 9-15 dm. tall, much branched: leaf- 

 blades 3 dm. long or more, 4-8 mm. wide, acuminate : panicle pyramidal, 1-3 dm. 

 long: spikelets about 2.5 mm. long, acuminate, the fourth scale on a delicate 

 stalk about 0.5 mm. long. — Common, in pastures and moist soil. — Sum. 



10. P. anceps Michx. Stems erect, 4-15 dm. tall, branched: leaf -blades 3 dm. 

 long or more, 4-10 mm. wide: panicles 1.5-3 dm. long: spikelets 2.5-3.5 mm. 

 long, lanceolate, acuminate, curved at the apex. — Common, in meadows and low 

 grounds. — Sum. 



11. P. linearlfolium Scribn. Stems tufted, slender, erect, simple, 1.5-4 dm. 

 tall: leaf -blades elongate, 7-25 cm. long, 2-4 mm. wide: primary panicle loose 

 and open, 4-10 cm. long: spikelets 2-2.5 mm. long, obtuse or acutish, pubescent 

 with spreading hairs. — Common, in dry soil, mostly on banks. — Sum. 



12. P. depauperatum Muhl. Stems erect, 3 dm. tall or less, simple: leaf -blades 



8-15 cm. long, elongate, 1-4 mm. wide: primary panicle much exserted, 2-8 

 cm. long, usually linear: spikelets 3-4 mm. long, glabrous, acute. — Common, on 

 dry banks. — Sum. 



13. P. dichotomum L. Light green, glabrous, or the lower nodes sometimes 

 barbed. Stems tufted, slender, 2-6 dm. tall, rarely taller, finally much branched 

 about the middle: leaf -blades widely spreading, linear-lanceolate, the primary 



