600 CLXI. GRAMINEJE. PSAMMA. 



long ; palea 5-veined, a little shorter than the upper glume ; sta. 3 ; stig. plu- 

 mose 7J. N. J. to Car. Aug. 

 /?. laxa. Panicle more loose, with long, green branches. White Mts. 



5. T. CONCINNA. Wood. (Agrostis concinna. Tuckm.} 



St. low, erect ; Ivs. filiform-setaceous ; pan. ovate, spreading, glabrous ; 

 gl. unequal, lower acute-mucronate, roughish above, upper acute, glabrous ; 

 palecB glabrous, awn from below the middle, contorted, scabrous, exceeding the 

 flower, with a few hairs at its base. White Mts. Tuckerman. The species are 

 not valuable in agriculture. 



9. M QHLENBERGIA. Schreb. 



In honor of the late Henry Muhlenberg, D.D., a well known, eminent botanist. 



Panicle nearly simple ; glumes 2, very minute, unequal, fringed ; 

 paleae many times longer than the glumes, linear-lanceolate, veined, 

 hairy at base ; the lower one terminating in a long awn. 



1. M. DIFFUSA. Schreb. Dorp-seed Grass. 



St. decumbent, diffuse, branching, slender, compressed ; branches assurgent ; 

 Ivs. 2 3' by 2", linear-lanceolate, rough, with smooth, striate, open sheaths ; 

 panicles terminal and lateral, with remote, appressed, rough branches ; spikelets 

 pedicellate, often purple ; awn about as long as the paleae. Tj. Borders of woods 

 and fields, N. Eng. to Car. and Ky. , Aug. 



2. M. ERECTA. Roth. (Brachyelytrum aristatum. Palis.') 



St. erect, simple, retrorsely pubescent at the nodes, 2 3i high ; Ivs. lanceo- 

 late, scabrous, ciliate on the margin, 4 6' long, 3" or more wide, with some- 

 what open sheaths ; panicle terminal, simple racemose, contracted ; spikelets 

 pedicellate, large ; glumes very unequal, upper one subulate ; lower paLete half as 

 long as its awn, upper palece with a short awn at base lodged in the dorsal 

 groove. 1\. Rocky hills, Can. and U. S., frequent. July. 



10. CINNA. 



Glumes 2, subequal, compressed, without involucre or awns, upper 

 one 3-veined ; paleae 2, naked at base, on short stipes, lower one 

 larger, enclosing the upper, with a short awn a little below the tip ; 

 stamen 1. 



C. ARUNDINACEA. Willd. (Agrostis Cinna. Lam. A. monandra. Hornem.} 

 St. simple, erect, smooth, 3 5f high ; Ivs. linear-lanceolate, 12 18' by 3 5" 

 pale green, rough-edged, with smooth, striate sheaths ; slip, long, lacerated ; 

 panicle near a foot in length, rather attenuated above and nodding, with the 

 branches capillary, drooping, and arranged somewhat in 4s ; glumes linear-lan- 

 ceolate ; lower palecc with a short, straight awn a little below the tip. % A 

 beautiful grass, sought by cattle, in rich, shady soils, U. S. and Can. Aug. 



11. TRICHOCHLOA. DC. 



Gr. rpt, Tpi%os, hair, %Xoa, grass ; from the capillary inflorescence. 



Glumes 2, very minute ; paleae many times longer than the 

 glumes ; naked at base, lower one convolute at base, terminating in 

 a long, unarticulated awn. 



T. "CAPILLARIS. DC. (Stipa. Lam. Agrostis. Muhl. Muhlenbergia. Lindl.) 

 Csespitose ; sts. erect, very slender and smooth, 18 24' high ; Ivs. erect", 

 becoming filiform towards the end. 1 Ijf long; panicle diffuse, with the 

 branches 1 4' long, in pairs, and as fine as hairs ; spikelets purple ; lower pakce 

 produced into an awn 3 or 4 times its length. <!}_ An exceedingly delicate grass, 

 with large, purple, glossy and almost gossamer-like panicles, waving in the 

 breeze. Sandy soils. Jn. Jl. 



12. PSAMMA. Palis. 



Gn fyanfios, sand ; in which this grass grows on the sea shore. 



Panicle spicate ; glumes 2, awnless; paleae 



