GRAMINACE^E. 429 



2. A. gracilis Ell. : culm very slender, erect ; panicle spiked, the flow- 

 er* appressed ; lateral awns rather shorter than the palese, erect ; middle 

 one longer, bent, not twisted ; lower palea spinulose on the keel. ( Torr. 

 N. Y. Fl.} A. stricta Darlingl. not of Mich. 



Sterile sandy soils. N. Y. to Car. Sept. (). Culm 415 inches high, 

 smooth. Leaves very narrow, convolute when dry. Panicle 2 5 inches long, 

 slender. A stricta Mich, is probably confined to the southern states. 



Slender Three-awned Grass. 



3. A. purpurascens Pair. : culm filiform, erect, simple ; leaves very nar- 

 row, flat ; flowers in a long spiked panicle ; awns nearly equal, twice as 

 long as the palese, divaricate. 



Sandy fields and woods. Mass, to Penn. \ Sept. %.. Culm 23 feet high, 

 Leaves filiform at the extremity. Panicle elongated, loose,purple. Introduced ? 



Purple Three-awned Grass. 



V. AGROSTE.E. Spikelets 1-flowered, rarely with the subulate rudi- 

 ment of an upper flower. Glumes and palea 2, membranaceoously 

 herbaceous ; lower palea often awned. Stigma mostly sessile. 



17. MUHLENBERGIA. Schreb. Muhlenbergia. 



(In honor of the late Henry Muhlenberg, D.D., one of the most distinguished 

 American botanists.) 



Glumes 2, very minute, unequal, one scarcely perceptible. 

 Paleae much longer than the glumes, linear-lanceolate, nerved, 

 hairy at base ; the lower one terminating in a long slender bris- 

 tle. Panicle more or less contracted. 



1 . M. diffusa Schnb. : culm decumbent, diffuse ; leaves linear-lanceolate ; 

 panicle slender, branched, the branches appressed ; bristles about twice as 

 long as the palea. 



Woods and pastures. N. Y. to Car. July. 1{-. Culm 12 18 inches long, 

 compressed, geniculate, branched. Leaves rough. Panicles terminal and lat- 

 eral, very slender ; bristle purplish. 



SpreadingMuhlenbergia. Drop-seed Grass. 



2. M. erecta Schreb. : culm erect, simple ; leaves lanceolate, pubescent ; 

 panicle simple, loose ; awn twice as long as the palea ; upper palea with 

 an awn at base lodged in a groove on the back. Drachyelytrum aristatum 

 Beauv. 



Rocky hills. Can. to Car. July. %.. Root creeping. Culm 23 feet high, 

 erect, slender. Leaves 4 6 inches long. Panicle simple, racemose, erect. 

 Lower palea with a very long awn. Erect Muhlenbergia. 



18. CINNA. Linn. Cinna. 

 (From the Greek Kiwa, a kind of grain.) 



Glumes nearly equal, compressed, the upper one 3 -nerved. 

 Paleoe 2, nearly equal, compressed, shortly stipitate, naked at 

 the base ; the lower one larger, enclosing the upper, with a 

 short awn near the summit. Stamen I, Panicle loose. 



