Descriptions of some new Grasses. 153 



smooth; Sheaths imbricate-carinate, smooth, deeply striate. 

 Stipule scarious, elongated and bifid. 



Panicle about an inch long, partly sheathed at the base, con- 

 tracted ; branches alternate, sub-simple, flexuous ; pedicels 

 incrassated upward ; flowers purplish, linear-lanceolate. 



Calyx two-glumed ; glumes sub-equal, a little longer than the 

 corolla, linear-lanceolate, attenuated into short bristles, or 

 cuspidate, smooth. 



Corolla two-valved, naked at the base, a little scabrous ; the 

 inferior valve terminating in an awn longer than the 

 flower. 



Stamens three. 



Hab. On the prairies of the Missouri and Piatt rivers. 

 Plant whitish. It resembles A. pungens and maritima, but 



differs entirely in its awned flowers. 



5. Andropogon glaucum.* 



Smooth, glaucous ; culm sub-simple ; nodes smooth ; pani- 

 cle terminal, much exsert, oblong ; spikes alternate, crowded ; 

 awns long, twisted ; abortive floret neuter, unarmed, one- 

 valved. 



DESCRIPTION. 



Culm two feet and more in height, nearly simple, very smooth. 

 Leaves broad-linear ; those on the culm about six inches long, 



very smooth on both sides, and of a glaucous hue. Sheaths 



nerved, shorter than the joints. Stipule obsolete. 

 Panicle on a long peduncle proceeding from the uppermost 



sheath, 4 — 5 inches long, rather compact ; spikes simple or 



branched, alternate ; rachis very villous. 

 Perfect fl. Cal. two-glumed, somewhat hairy ; glumes 



acute, entire ; the inferior hairy towards the base ; superior 



naked. 



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