OKDKR CXLII. GKAMIXACEJE. 585 



digitate, 3 — 5 ; paleae longer than tlie rudiment. — An introduced grass. 

 Very difficult to exterminate, especially in loose, rich soil. 



Bermuda Grass. Digitaria dactylon, Ell. 



Gents XX.— CHLO'RIS. Schwartz. 

 (From chloros, green, in allusion to its herbage.) 



Flowers polygamous. Glumes 2, 2-flowered ; one of them 

 perfect and sessile, the other staminate. Palea? of the perfect 

 flower 2. awned. Spikes by fours, digitate. 



1. C. petr.e'a, (Ell.) (Eustachys petrcea, Desv.) Stem prostrate, 

 branching, assurgent, geniculate. Leaves glabrous, with the margins 

 an 1 midrib serrulate. Glumes 2, 2-flowered ; exterior glume awned, 

 the interior smaller, keeled. Palea of the sterile floret concave, ob 

 tuse. — If. June — Aug. On the sea-coast. 



Genua XXL— ELEUSLXE. Gasrt 



(From Eleusin, the name of a town where Ceres was worshiped.) 



Flowers on one side of the rachis. Glumes 2, unequal, 5 — 7- 

 flowered. Palece 2, obtuse, upper one bifid. Scales fimbriate. 

 Sjyikes digitate. 



1. E mucrona'ta, (Mich.) (Leptochloa- mucronata, Kunth.) Stem 

 erect, glabrous. Leaves slightly scabrous, with hispid sheaths longer 

 than the joints. Panicle long, with the spikes -i — 5 inches long. Glumes 

 nearly equal, with colored keels. Palece unequal, the exterior hairy. — 

 0. July — Oct. Cultivated lands. 1 — 3 feet. 



2. E. in'dica, (Gaert.) Stem decumbent, lucid. Leaves linear, with 

 the under surface glabrous, long ; sheaths pubescent, compressed. 

 Spikes usually 5, digitate, one below the rest ; spikelets usually 5-flow- 

 ered. Glumes unequal, with the keels scabrous. — If. June — October. 

 Common. 1 — 2 feet. 



3. E. crucia'ta. (Dactyloctemum jEgyptiacum, Willd.) Stem de- 

 cumbent and assurgent, glabrous. Leaves narrow, ciliate. Spikes 2 — 

 4; spikelets usually 3 flowered, the terminal one usually sterile or 

 wanting ; extremity of the rachis naked. — @. July. Common. 12 — 

 18 inches. 



Genus XXIL— MOXOCE'RA. Ell. 



(From monos, one, and keros, horn ; there being but one spike.) 



Flowers polygamous, on one side of the rachis. Glumes 2, 

 many-flowered, awned below the summit. Palece of the per- 

 fect flower 2-valved, unequal ; the exterior one awned below 

 the summit ; those of the sterile flower unawned. 



1. M. aromat'ica, (Ell.) (Ctenium Americanum, Sprig.) Stem pu- 

 bescent, ereet. j >rous on the upper surface, glabrous be- 

 neath; sheaths shorter than the joints, hairy at the throat. Spikes ter- 

 minal, s..-cund ; spikelets in 2 lows. Glumes 3-flowered; the exterior 

 glume with an awn projecting from the center of the back ; the inferior 

 palea small, pubescent. — If. May — July. Pine-barrens. 



Toothache-grass. 



