_ GRAMINEAE. 83 



acuminate, about one-half as long as the spikelet, 3-5 -nerved; second scale gen- 

 erally longer than the others, 5~7-nerved, the third similar and usually subtending 

 a palet and stamina te flower. In moist or dry soil, Me. and Ont. to Minn., south 

 to Fla., Kans. and Tex. Aug.-Sept. ** '*? 



10. Panicum amarum Ell. SEA-BEACH PANICUM. (I. F. f. 271.) Smooth and 

 glabrous, glaucous; culms arising from long branching rootstocks, 3-9 dm. tall, de- 

 cumbent. Sheaths overlapping; leaves 1.5-3 dm. long, 6-12 mm. wide, long-acumi- 

 nate, thick and leathery, involute on the margins, at least toward the apex, the 

 uppermost leaf generally exceeding the panicle; panicle linear, less than 3 dm. 

 long, its branches erect; spikelets 5-6 mm. long; first, second, and third scales 

 acuminate, the first one-half to two-thirds as long as the spikelet, the third some- 

 what longer than the second, usually with a palet and staminate flower, the fourth 

 elliptic. On sea beaches, N. H. to Fla. Sept.-Nov. 



11. Panicum agrostoides Spreng. AGROSTIS-LIKE PANICUM. (I. F. f. 249.) 

 Culms erect, 4.5-6 dm. tall, much branched, compressed, smooth. Sheaths com- 

 pressed, glabrous, or sometimes hairy at the throat; ligule very short, naked; 

 leaves 3 dm. long or more, 4-8 mm. wide, acuminate; panicles pyramidal, 1-3 

 dm. long, terminating the culm and branches; primary branches of the panicle 

 spreading, secondary generally appressed; spikelets 1.5 mm. long, acute, straight; 

 first scale 3 -nerved, acute; second and third scales 5 -nerved, about twice as long 

 as the first and longer than the oval fourth scale. Wet ground, Me. to Minn., 

 south to Fla., Kans. and Tex. July-Sept. 



12. Panicum longifolium Torr. LONG-LEAVED PANICUM. (I. F. f. 251.) 

 Culms erect, 3-6 dm. tall, slender, simple, or occasionally with a single lateral 

 panicle. Leaves 2-3 dm. long, 2-4 mm. wide, acuminate into a long, slender 

 point, rough, glabrous; ligule short, pilose; panicles 1.25-2.25 dm. long; primary 

 branches long and slender, spreading, secondary very short, appressed, generally 

 bearing 1-3 spikelets; spikelets 2 mm. long, acuminate; first scale acute, about 

 one-half as long as the acuminate second one; third scale equalling the second, 

 acuminate, one-third longer than the elliptic obtuse fourth one. Moist soil, Conn, 

 to Penn. and D. C. Aug-Sept. 



13. Panicum rostratum Muhl. BEAKED PANICUM. (I. F. f. 248.) Culms 

 erect from a creeping scaly branched rootstock, 4.5-15 dm. tall, much branched. 

 Sheaths glabrous, or the lower ones pubescent; leaves 3 dm. long or more, 4-10 

 mm. wide, acuminate; panicles pyramidal, 1.53 dm. long; axis and ascending 

 branches scabrous; spikelets 3 mm. long, crowded, lanceolate, acuminate; first 

 scale less than one-half as long as the spikelet; second scale curved at the apex, 

 scabrous above on the middle nerve; third scale usually subtending a small empty 

 palet. Moist soil, N. J- to 111. and Kans., south to Fla. and Tex. July-Sept. 



14. Panicum stipitatum Nash. LONG PANICUM. (I. F. {. 250.) Culms 

 erect, 9-15 dm. tall, much branched. Leaves 3 dm. long or more, 4-8 mm. wide, 

 acuminate, scabrous; panicles pyramidal, 1-3 dm. long; primary branches spread- 

 ing or ascending, the secondary usually divaricate; spikelets about 2.5 mm. long, 

 crowded, acuminate; first scale acute or acuminate, one-third the length of the 

 equal and acuminate second and third; fourth scale narrowly elliptic, about one- 

 half as long as the third and raised on a delicate stalk about 0.5 mm. long. Moist 

 soil, N. J. and Penn. to Ky., Tenn. and N. Car, July Sept. (P. elongatiim Pursh. 

 Not Salisb. 1796.) 



15. Panicum depauperatum Muhl. STARVED PANICUM. (I. F. f. 268.) 

 Culms erect, 3 dm. tall or less, simple or branched at base. Sheaths glabrous to 

 hirsute; leaves erect, elongated, 1-4 mm. wide, mostly crowded at base and equal- 

 ling or one-half as long as the culm, the upper culm-leaf often much exceeding the 

 panicle; primary panicle generally much exserted from the upper sheath, 2.5-7.5 

 cm. long, usually linear, its branches mostly erect; secondary panicles on very 

 short basal branches and often concealed by the lower leaves ; spikelets 3- 4 mm. 

 long, glabrous, acute. In dry places N. S. to Manitoba, south to Fla. and Tex. 

 June-Sept. 



16. Panicum Enslini Trin. LINEAR-LEAVED PANICUM. (I. F. f. 268a.) 

 Culms tufted, very slender, erect, smooth and glabrous, simple, 1.5-4 dm. tall. 

 Sheaths glabrous or pilose with long white hairs; leaves elongated, glabrous or 

 more or less pilose, especially upon the lower surface, 7.5-25 cm. long, 2-4 mm. 



