558 GRAMINEJE. (GRASS FAMILY.) 



less. Glumes 2, membranaceous, very unequal ; the larger upper one with a 

 spreading awn or tubercle on the back. Paleae of the perfect flower membrana- 

 ceous ; the lower one awned below the apex, and densely ciliate on the margins- 

 Stamens 3. Ovary smooth. Styles terminal : stigmas elongated, plumose, with 

 simple hairs. Grain free. 



1. C. Americanum, Sprcng. Root pungent; culm (2° -3° high) rough, 

 like the narrow leaves; spike at length recurved or coiled (3' -4' long) ; upper 

 glume granular on the back ; the stout awn spreading horizontally. (Monocera 

 aromatica, Ell ) — Low pine barrens, Florida to North Carolina. July and 

 Aug. U- 



21. DACTYLOCTENIUM, Willd, Crowfoot-Grass. 



Annual creeping or spreading branching grasses, with flat leaves and digitate 

 rarely single spikes. Spikelets 2 - several-flowered, crowded on one side of the 

 flattened rachis ; the uppermost flower imperfect. Glumes 2, compressed-keeled, 

 membranaceous ; the upper (exterior) awn-pointed. Paleae 2, boat-shaped, 

 pointed. Stamens 3. Stigmas plumose, with branching hairs. Grain round- 

 ish, rugose, free. 



1. D. JEgyptiacum, Willd. Culms ascending from a creeping base; 

 leaves fringed ; spikes commonly 4, awn-pointed ; spikelets 3-flowered. (Elcu- 

 sinc'? cruciata, Ell.) — Cultivated ground, common. Introduced. ■ — Culms nu- 

 merous, 1° high. Spikes 1'- 2' long. 



22. ELEUSINE, Gaert. 



Characters chiefly of Dactyloctenium, but the narrower glumes and paleae 

 obtuse and awniess. Stigmas plumose, with simple hairs. Spikelets closely 

 imbricated. — Low annuals. 



I. E. Indica, Gaert. — Cultivated ground, very common. Introduced. 

 Culms (6' -18' high) flattened; leaves flat; spikes 2 -several, the lower ones 

 sometimes scattered (2' -4' long) ; spikelets 6-flowered. 



23. LEPTOCHLOA, Beauv. 



Flat-leaved grasses, with the numerous spikes disposed in a terminal raceme. 

 Spikelets sessile, loose on one side of the elongated filiform rachis, 3 - many- 

 flowered. Glumes 2, membranaceous, unequal, keeled. Paleae 2, membrana- 

 ceous ; the lower one longer than the upper, 3-nerved, awned or unawned. 

 Stamens 3. Grain oblong, free. 



§ 1. LEPTOCHLOA Proper. — Lower palca unowned. 

 1. L. mucronata, Kunth. Culms 2° -3° high ; sheaths of the broad (4"- 

 6" wid.) rough leaves hairy; spikes numerous, in an elongated raceme, 2' -4' 

 long, spreading; spikelets minute, 3 -4-flowered ; glomes mucron ate, longer or 

 shorter than the flowers ; lower palea smooth, cmaiginate. (Elensine mucro- 

 nata. Michx.) — Cultivated fields, Florida, and northward. Aug. -Sept. © 



