748 GRAMINEjE fhbagmitbs 



dactylis 



horizontal perennial rootstocks, glabrous : sheaths shorter than the inter- 

 nodes, loose : ligules a ring of very short hairs : leaves 6-18 inches long, 4-9 

 lines wide : spikelets crowded on the ascending branches : first glume 1- 

 nerved, %-% as long as the second one : flowering glumes 5-6 lines long, 

 3-nerved, long-acuminate, equalling the hairs of the rachella. In bogs 

 and wet places nearly throughout North America : also in Europe and Asia. 



35 DACTYLIS L. Sp. 71. 



Tall perennial grasses with broad flat leaves and numerous 

 spikelets crowded in paniculate short capitate clusters. Spikelets 

 3-5-flowered, all perfect or the upper staminate, the two lower 

 glumes empty, thin-membranaceous, keeled, unequal, mucronate. 

 Flowering glumes longer than the empty ones, rigid, 5-nerved, 

 keeled, the midnerve extended into a point or short awn. Palets 

 shorter than the glumes, 2-keeled. Stamens 3. Styles distinct. 

 Stigmas plumose. Grain free, enclosed in the glume and palet. 



D. glomeeata L. Sp. 71. Stems simple, erect, 2-4 feet high : sheaths 

 shorter than the internodes : smooth or rough : ligules 1-2 lines long : 

 leaves 3-9 inches long, 1-3 lines wide, flat, scabrous : panicle 3-8 inches 

 long, its branches spreading or ascending in flower, erect in fruit, the lower 

 1-3 inches long, spikelet bearing from about the middle : spikelets in dense 

 capitate clusters, 3-5-flowered : empty glumes 1-3-nerved, the first shorter 

 than the second: flowering glumes 2-3 lines long, rough, pointed or short- 

 awned, ciliate on the keel. In fields and waste places, naturalized from 

 Europe. 



36 KCELERIA Pers. Syn. i, 97. 



Tufted perennial or annual grasses with flat or setaceous leaves 

 and numerous spikelets in spike-like panicles. Spikelets 2-5-flow- 

 ered. Glumes 4-7, the two lower empty, narrow, acute, unequal, 

 keeled, scarious on the margins. Flowering glumes 3-5-nerved. 

 Palets hyaline, acute, 2-keeled. Stamens 3. Styles very short, 

 with plumose stigmas. Grain free, enclosed in the glume. 



K. cristata Pers. 1. c. Stems erect, simple, rigid, often pubescent 

 just below the panicle : sheaths often shorter than the internodes, smooth 

 or scabrose. sometimes hirsute : ligules % line long : leaves 1-12 inches long, 

 %-\% lines wide, erect, flat or involute, smooth or rough, often more or 

 less hirsute : panicle 1-7 inches long, pale green, usually spike-like, the 

 branches erect or rarely ascending, 1 inch long or less : empty glumes une- 

 qual, the first one about 2 lines long, scarious except the green keel; second 

 one longer, scabrous on the keel; flowering glumes scarious, l>£-2 lines 

 long. On sandy bars along rivers. California to Brit. Columbia and 

 Pennsylvania. 



37 EATONIA Raf. Journ. Phys. lxxxix 104. 



Tufted perennial grasses with flat leaves and usually contract- 

 ed panicles. Spikelets 2-3-flowered, the rachella extended beyond 

 the flowers. Two lower glumes empty, shorter than the spikelet, 

 the first linear acute, I -nerved, the second much broader, 3-nerved, 

 obtuse or rounded at the apex or sometimes acute, the margins. 

 scarious : flowering glumes narrow, usually obtuse. Palets narrow, 

 2-nerved. Stamens 3. Styles distinct, short. Stigmas plumose. 

 Grain free loosely enclosed in the glume and palet. 



