604 CLXI. GRAMINE^E. PANICUM. 



tered, horizontal, 1 6' long ; spikelets ovate, few and scattered ; pokes smooth 

 and polished. 1\. In woods, Penn. to Can. Plant pale green. Summer. 



2. M. PUNGENS. Torr. Dwarf Mittet Grass. 



St. erect, simple, rigid, 12 18' high ; Ivs. lanceolate, cauline very short, 

 pungent, at length involute, radical 6 8' long, erect, acute and pungent; sheaths 

 striate, rough, tumid ; panicle contracted, few-flowered ; ped. bifid ; glumes awn- 

 less ; palece hairy, about equaling the glumes ; sty. 2-parted. 1L Rocky hills, 

 Northern States, rare. May. 



3. M. AMPHICARPON. Pursh. (M. ciliatum. Muhl.) 



Sts. numerous, assurgent, 18 24' high, somewhat branched and genicu- 

 late ; Ivs. 2 3' by 2 4", lance-linear, hairy and ciliate ; sheaths striate, the 

 upper ones leafless ; panicle simple, 2 3' long, its branches few, erect, appressed, 

 racemose, bearing $ flowers; spikelets oblong, purplish; radical peduncles clus- 

 tered, 13' high, sheathed, each bearing a single 9 spikelet ; caryopsis brown. 

 N. J. Aug. 



20. OPLISMfiNUS. Kunth. 

 Gr. oTrAiffji/a, armament, pevos, courage; alluding to the stout awns. 



Panicle compounded of alternate, dense racemes ; glumes 2, une- 

 qual, echinate, 2-flowered, lower short, upper as long as the , acumi- 

 nate ; abortive flowers with 2 paleae, the lower terminating in a long 

 awn ; $ paleae cartilaginous, shining, coating the caryopsis. 



1. O. CRUS-GALLI. Kunth. (Panicum. Linn.) Cock's-foot Grass. 



St. terete, smooth, 3 4f high ; Ivs. linear-lanceolate, flat, serrulate, with 

 smooth, striate sheaths and no stipule ; panicle simple or apparently so, branches 

 spike-form, compound, alternate and in pairs ; rachis hairy and rough ; glumes 

 hispid with bristles ; lower abortive palea ending in a rough awn, nearly 1' in 

 length. (J) A coarse, weedy grass, introduced into cultivated grounds, barn- 

 yards, &c., common. Aug., Sept. 



2. O. HISPIDUM. Wood. (O. nmricatus. Kunth. Panicum. Muhl.) 



St. thick, 3 4f high ; Ivs. broad, flat ; panicle compound, nodding, dense, 

 4 6' long, with alternate racemes ; fls. always awned. (J) Salt marshes, N. Y. 

 to Car. Best distinguished from the preceding by its hispid sheaths. Sept., 

 Oct. 



21. PAN I CUM. 

 Lat. panicula, the mode of flowering, or panis, bread, which some species afford. 



Glumes 2, unequal, the lower mostly very small ; flowers 2, dis- 

 similar, the lower abortive or sterile, with 1 2 paleae, the upper 

 palea membranaceous ; the upper , with the paleae cartilaginous, 

 equal, concave, awnless, coating the caryopsis. 



* Spikelets in racemose panicles. 



1. P. AGRQSTolDEs. Muhl. (P. elongatum. Ph. P. fusco-rubens 1 Nutt.) 

 St. compressed, glabrous, 1| 3f high, often geniculate at base ; Ivs. long 



and numerous, cauline linear-lanceolate, carinate, rough-edged, on short, striate 

 sheaths; panicles terminal and lateral, pyramidal, composed of racemed, 

 spreading or deflexed branches ; spikelets 1" long, purple, lanceolate, acute, 

 crowded and appressed; upper glume 5- veined; palea of the neutral flower 

 nearly equal. 1\. 7 Meadows, frequent. July. 



2. P. ANCEPS. Michx. (P. rostratum. Muhl.} 



St. compressed, 2 3f high ; Ivs. linear, carinate, very long ; sheaths an- 

 cipital, pilose on the throat and margin ; panicle erect, contracted, with nearly 

 simple branches ; spikelets interruptedly racemose, very acuminate ; upper palea 

 of the neutral flower oblong, obtuse or emarginate. % Fields and meadows. 

 Common, Mid. States, N. Eng. July. 



3. P. PROLIFERUM. Lam. (P. dichotomiflorum. MX. P. geniculatum. 

 Muhl.) St. assurgent, geniculate at base, very smooth, thick and succu- 

 lent ; Ivs. linear-lanceolate, 4 6" wide, 10 15' long, on tumid sheaths, hairy 



