Twenty-fib st Annual Meeting. 99 



44. Diakbhena Raf. 

 a. Simple culm with long, linear-lanceolate flat leaves at base 127 



127. Diarrhena Americana Beauv. 



45. Uniola L. 

 a. The very broad, flat spikelets on drooping pedicels 128 



128. Uniola latlfolia Mx.; Broad-flowered Fescue grass. 



46. Distiohlis Raf. 

 a. Leaves rigid and sharp-pointed, glumes many-nerved, coriaceous 12& 



129. Distichlis maritima Raf.; Salt grass, Marsh grass. 



47. Dactylis L. 

 a. Upper branches of panicle short, lower, longer and spreading 130 



130. Dactylis glomerata L.; Orchard grass, Cock's-foot grass. 



48. Poa L. 



a. Flowering glumes compressed-keeled, acute (c). 

 a. Flowering glumes rounded on the back, obtuse {b). 



b. Spikelets 3-7-flowered, outer glumes acute, rough on the back 131 



b. Spikelets mostly 3-flowered, outer glumes very acute, rough on the mid-nerve 132 



c. Low and spreading, 3-6 in. high, from an annual or biennial root, flaccid 133 



c. Culms 6-20 in. long, geniculate-ascending, rigid, very much flattened 134 



d. Spikelets mostly numerous, and crowded on rather short, rough branches (e). 



d. Spikelets fewer and more scattered on slender pedicels, flowering early (/). 



e. Ligules elongated, flowering glume very obscurely nerved, spikelets narrow. 135 



e. Ligules short and blunt, flowering glume 5-nerved, hairy along the margin and keel 136 



e. Ligules oblong, acute, flowering glume prominently 5-nerved, naked at the margins 137 



/. Spikelets 3-4 lines long, flowering glume conspicuously scarious-tipped 140 



/. Spikelets 1-2 lines long, flowering glume scarcely scarious-tipped (g). 



g. Flowers oblong, obtuse, branches of panicle in fives or more 13S 



g. Flowers and glumes acute, branches of panicle in threes or fours 139 



131. Poa andina Nutt.; Mountain Spear grass. 



132. P. tenuifolia Nutt.; Oregon Blue grass. 



133. P. annua L.; Annual Spear grass, Goose grass. 



134. P. compressa L.; Wire grass, Blue grass. 



135. P. serotina Ehr.; Fowl Meadow grass, False Red-Top. 



136. P. pratensis L.; June grass, Ky. Blue grass, Spear grass, Meadow grass. 



137. P. trivialis L.; Rough-Stalked Meadow grass. 



138. P. sylvestris Gr.; Meadow grass, Spear grass. 



139. P. alsodes Gr.; Tall Blue grass, Wood Spear grass. 



140. P. flexuosa Muhl.; Meadow grass, Spear grass. 



49. Gltceeia R.Br. 



a. Flowering glume conspicuously nerved, styles present (b). 



a. Flowering glume inconspicuously 5-nerved, stigmas nearly sessile 145 



b. Spikelets linear, i inch long, appressed, terete; panicle narrow 144 



b. Spikelets ovate, oblong, or liuear-oblong, 1-3 lines long (c). 



c. Spikelets ovate, at length very broad and tumid, 2 lines long 141 



c. Spikelets very numerous, ovate-oblong, 3-7 flowered, 1-2 lines long 142 



c. Spikelets obloDg, or linear-oblong, 5-9 flowered, about 3 lines long 143 



141. Glyceria Canadensis Trin.; Rattlesnake grass, Tall Quaking grass. 



142. G. nervata Trin.; Nerved Meadow grass, Nerved Manna grass. 



143. G. aquatica Sm.; Reed Meadow grass, White Spear grass. 



144. G. fluitans R. Br.; Floating Manna grass. 



145. G. distans Wahl. ; Manna grass. 



