TRIANDRIA DIGYNIA 53 



!, A. dichotoma, Mx. Culm cespitose, dichotomously branching ; 



panicle contracted, racemose ; lateral awns very short; the intermediate 



one nearly as long as the palea, contorted. Beck, Bot. p. 400. Spe- 



cim. Gray, Gram. 1. no. 7. 



Forked Aristida. Vulgo — Poverty Grass. 



Root perennial ) (annual or biennial, Torr.) CulmOto 15 inches long, slender, 

 often oblique, or decumbent, geniculate, branching somewhat dichotomously at the 

 joints, glabrous. Leaves flat, narrow, with setaceous points, minutely serrulate ; 

 sheaths very short, open, pilose at throat ; UguU very short. Sjnkelets elongated, 

 slender, disposed in racemes, on clavate peduncles. Glumes lance-linear, cuspi- 

 date, a little longer than the palea (shorter, Torr.). Upper palea obsolete, or none; 

 lower one involute, terete, on a short pubescent pedicel ; lateral aims straight, not 

 one fourth the length of tfie palea, middle one contorted, or Dent horizontally. 



Hub. Dry sterile soils : Mica-slate hills : frequent Fl. Aug. JFV- Sept. 



2. A. stricta, Mx ? Culm and leaves strictly erect ; panicle slender 

 racemose, spikelets appressed ; lateral awns straight, erect; the middle 

 one longer, at first erect, finally spreading. Beck ? Hot. p. 400. 

 Upright Aristida. Vulgd — Poverty Grass. 



Root perennial? Culm erect, setaceously slender, 12 to 13 inches high, glabrous. 

 Leaves setaceous, erect, convolute towards the extremity ; sheaths short, sparing- 

 ly pilose, with long hairs at throat ; ligule short. Spikclets acicular, in a slender, 

 erect, racemose panicle. Ghunes nearly equal, very acute. Palea single 1 close- 

 ly involute ; awns very scabrous ; the lateral ones erect, shorter than the palea, tho 

 middle one longer than the palea, at first erect, finally oblique. 



Hah. Dry sterile old fields: frequent. Fl. August. Ft. September. 



Obs. Our plant does not quite agree with the descriptions in the books, — and in 

 its more advanced stages, seems to approach the preceding: but I have supposed 

 it to be the A. stricta, or a variety of it. Seven or eight additional species are enu- 

 merated in the U. States. They are grasses of no value ; and always indicative - 1 

 a poor soil. 



Div. III. Agrostideje — Jlgrostis, or Herd's Grass Tribe. 



Inflorescence mostly Panicled, sometimes Spiked. Spikelets solitary, l-towt > - 

 ed. Glumes and Pale© of nearly similar texture % usually keeled. 



a. Flowers Jtfonandrous. 



31. CINNA. L. JYutt. Gen. 69. 

 [Greek, Kein, to heat; a supposed quality of the plant.] 



Glumes 2, nearly equal, compressed, the upper one 3-nerved. Palest 

 2, compressed, shortly stipitate, naked at base ; lower one larger, en- 

 closing the upper, with a short awn near the summit. 



1. C. arundinacea, IViUd. Culm simple, glabrous; leaves linear- 

 lanceolate ; panicle large, loose, with the branches somewhat in four's, 

 capillary. Beck, Bot. p. 390. 

 Agrostis Cinna. Pursh, Jim. 1. p. 64. 

 Muhlenbergia Cinna, Gray, Gram. I. Specie no. 16. 



RlSED-LIKE (JlSSA. 



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