646 GRAMINKjB. (GRASS FAMILY.; 



branches densely spiked-clustered, linear (green and purplish) ; glumes awnless, sharp 

 pointed, unequal, the upper about the length of the very acute lower palea, 

 (Agr. Mexicana, L. A. laterifiora, Miclix.) Varies with more slender pani- 

 cles (A. filiformis, Muhl.) Low grounds; common. Aug. 



# * Lower palea Irrislle-awned from the tip : flowers short-pedicelled. 



4. M. sylvdtica, Torr. Gr. Culms ascending, much branched and 

 diffusely spreading (2 -4 long); contracted panicles densely many-flowered; 

 glumes almost equal, bristle-pointed, nearly as long as the lower palea, which bears an 

 awn tw"ice or thrice the length of the spikelet. (Agr. diffusa, Muhl.) Low 01 

 rocky woods ; rather common. Aug., Sept. Aspect between No. 3 and No. 5. 



5. HI. Wiilcleiiovii, Trin. Culms upright (3 high), slender, simple or 

 sparingly branched ; contracted panicle slender, loosely flowered ; ylumes slightly 

 unequal, short-pointed, half the length of the lower palea, which bears an awn 3-4 

 times the length of the spikelet. (Agr. tenuiflora, Willd.) Rocky woods; 

 rather common. Aug. 



6. M. diffusa, Schrcber. (DROP-SEED. NIMBLE WILL.) Culms dif- 

 fusely much branched (8' -18' high) ; contracted panicl.es slender, rather loosely 

 many-flowered, terminal and lateral ; glumes extremely minute, the lower obsolete^ 

 the upper truncate ; awn once or twice longer than the palea. (Dilepyrum 

 minutiflorum, Michx.) Dry hills and woods, from S. New England to Michi- 

 gan, Illinois, and southward. Aug., Sept. Spikelets much smaller than in the 

 foregoing, 1" long. 



$ 2. THICH6CHLOA, DC. Panicle very loose and open; the long branches and 

 pedicels capillary : leaves narrow, often convolute-bristle-form. 



7. M. capillaris, Kunth. (HAIR-GRASS.) Culm simple, upright (2 

 high) from a fibrous (perennial?) root; panicle capillary, expanding (6' -20' 

 long, purple) ; glumes unequal, J to ^ the length of the long-awned palcae, the 

 lower mostly pointless, the upper more or less bristle-pointed. Sandy soil, W. 

 New England to New Jersey, Kentucky, and southward. Aug. Pedicels V - 

 2' long, scarcely thicker than the awns, which are about 1' long. 



11. BRACHYELYTRUM, Beauv. BRACHYELYTRUM. 



Spikelets 1-flowered, with a conspicuous filiform pedicel of an abortive second 

 flower about half its length, nearly terete, few, in a simple appressed racemed 

 panicle Lower glume obsolete ; the upper minute, pointless, persistent, shortei 

 than the wi 1th of the thick stalk of the flower. Paleaj chartaceo-herbaceous, in- 

 volute, enclosing the linear-oblong grain, somewhat equal, rough with scattered 

 short bristles ; the lower 5-nerved, contracted at the apex into a long straight 

 awn ; the upper 2-pointed ; the awn-like sterile pedicel partly lodged in the groove 

 on its back. Stamens 2 : anthers and stigmas very long. A perennial grass, with 

 simple culms (l-3 high) from creeping rootstocks, downy sheaths, broad and 

 flat lanceolate pointed leaves, and large spikelets ' long without the awn. (Name 

 composed of jSpa^us, short, and eAvrpoi/, husk, from the very short glumes.) 



1. B. aristatum, Beauv. (Muhlenbcrgia erecta, Schreb. Dilepyrum 

 aristosum, Michx.) Rocky woods; rather common. June. 



