TRICHODIUM. CLX1. GRAMLNE^E. 599 



6. SPOROB6LUS. Brown. 



(ff. ffiropa, a seed ; p uXXw, to cast forth ; its fruit is loose, and easily falls out. 



Panicles contracted ; glumes 2, glabrous, awnless, unequal, one or 

 both much shorter than the paleae ; paleae 2, concave, nearly equal, 

 beardless ; fruit loose, free, not enclosed in the paleae. 



S. ASPER. Sullivanf? 



Rt. long, white, fibrous ; st. stout, glabrous, geniculate at base, 2f high j 

 Ivs. rigid, glabrous, 2 8' by 1 3", tapering to a long, pungent point ; branches, 

 with short leaves, barren, also ending in a long, pungent point ; sheaths ciliate at 

 edge and bearing dense tufts of long, white hairs at top ; panicles small, terminal 

 and lateral, half enclosed in the long sheaths ; spikelets blackish-green ; lower 

 glume very short, upper nearly as long as the paleae ; fr. compressed, obovate, 

 J" in length, %. Ohio, Sullivant! 



7. POLYPOGON. Desf. 



Gr. jroXvf , many, irtoywv, beard ; a characteristic term. 



Inflorescence contracted into a spike; glumes 2, nearly equal, 

 obtuse, with long awns ; paleae shorter than the glumes, lower one 

 entire, with a short, straight, tender awn (sometimes awnless), upper 

 one bifid, toothed. 



P. RACEMOsus. Nutt. (P. glomeratus. Willd. Agrostis racemosus. MX. 



Muhlenbergia glomerata. Trin.) Glaucous; st. compressed, erect, smooth, 

 with appressed branches or subsimple, 1 J If high ; Ivs. somewhat 2- rowed, erect, 

 flat, rough, 3 5' long, with closed sheaths ; panicle spicate, dense, conglome- 

 rated, interrupted, 2 -3' long, many-flowered ; glumes linear, | the length of 

 their awns ; lower palea mucronate. 1{. Bog meadows, also on rocky mountains 

 N. Eng. to Mo. ! Aug., Sept. 



8. TRICHODIUM. 



Gr. $pt, rpiKOf, hair; from its capillary inflorescence. 



Inflorescence a capillary panicle ; glumes 2, subequal, narrow and 

 acute ; palea 1 (or 2, the upper very minute), awnless. shorter than 

 the glumes, loosely enclosing the caryopsis. 



1. T. LAXiFLdRUM. Michx. (Agrostis Michauxii. Trim,.} Thin grass. 



St. erect, smooth, very slender, 1 2f high ; Ivs. 3 6' long, linear-lanceo- 

 late, scabrous, lower ones involute, upper ones shorter and flat ; sheath rather 

 open ; panicle large and very diffuse, with long, capillary, verticillate branches, 

 trichotomously divided near the end ; spikekls in terminal clusters, purple ; glumes 

 linear-lanceolate. 1\. Pastures and roadsides, U. S. and Brit. Am. Jn. 



2. T. MONTANUM. Torr. (Agrostis Torreyi. Tuckm.) Mountain Hair Grass. 

 Sis. ceespitose, erect, filiform, simple, in small tuns, 8 12' high; radical 



Ivs. 2 3' long, involute-filiform, cauline rather longer ; stip. bifid, serrate ; pan. 

 ovate, branches spreading, finally divaricate, capillary, hispid ; spikelets fascicu- 

 late at the ends of the branches ; glumes equal ; palea with a short, twisted awn 

 at the back. 7J. Mts. and rocky woods, N. H. and N. Y. 



3. T. SCABRUM. Muhl. (Agrostis scabra. Wttld.) Rough Hair Grass. 



St. geniculate at base, assurgent, branched, 1 2f high ; Ivs. rough, striate, 

 linear-lanceolate, 4 6' long, with the sheaths commonly closed and smooth ; 

 panicle long, with verticillate, divaricate, dichotomously divided branches which 

 are much shorter than in T. laxijlorum ; spikelets pale green, not clustered. QJ. 

 Common in dry soils, N. Eng. to 111. July. 



4. T. ALTISSIMUM. Michx. (T. elatum. Ph. Cornucopias alt. Watt.) 



St. erect, rigid, simple, slender, 3f high, leafy ; Ivs. broadly linear, sca- 

 brous flat, 68' long ; sheaths scarcely smooth ; panicle purple, exserted, con- 

 tracted, branches in whorls of 4s 6s, erect, rather rigid, and dense-flowered at 

 the ends; glumes subequal, lanceolate, acuminate, scabrous on the keel, about J" 

 51 



