22 THE AMERICAN MIDLAND NATURALIST 



3. Panicles numerous, rather short, somewhat dense or more 

 or less open; lemmas not awned. 4. 



4. Panicles numerous, rather short, more or less dense; lemmas 

 not awned, perfectly glabrous. 8. MuhlEnbergia glabriflora 



4. Panicles numerous, more or less open, often slender; lemmas 

 not awned, pubescent at the base; infranodes perfectly smooth; 

 nodes glabrous. 9. Muhlenbergia Mexicana. 



5. Panicles few, short, dense, glomerate, oblong or cylindrical; 

 flowers usually purplish; lemmas awn-pointed or somewhat 

 aristate; glumes mucronate or aristate, subequal; infranodes 

 retrorsely scabrous: nodes glabrous. 



10. Muhlenbergia foliosa. 



5. Panicles numerous or sometimes fewer, filiform, linear or 

 oblong, dense or rather loose. 6. 



6. Panicles usually few, usually short-exserted, linear or fili- 

 form; infranodes retrorsely scabrous; nodes glabrous; flowers 

 not crowded, in rather long, erect branches, usually green or 

 stramineous; spikelets 2.5-3mm. long; lemmas usually long- 

 awned, or rarely awnless. 11. MuhlENBergiaTorreyi. 



6. Panicles numerous, dense, slender, elongated, usually long- 

 exserted; infranodes minutely scabrous or nearly glabrous; lem- 

 mas acuminate, rarely awned, villous with very long hairs at the 

 base; spikelets 2-2. 5mm. long. 12. Muhlenbergia polystachya. 



D. EucLADiTjM section nova. 



Culms strictly erect, not rooting at the lower nodes, minutely 

 retrorsely puberulent; glumes broad, one-half as long as the spike- 

 let or more, acuminate or cuspidate; lemmas awnless, long-acum-. 

 inate or cuspidate; no creeping scaly rootstocks; panicles slender, 

 the branches appressed. 13. Muhlenbergia cuspidata. 



I. Muhlenbergia vSchreberi J. F. Gmelin, vSyst. Nat. 2:171. 

 1791. 



Muhlenbergia diffusa Willd. vSp. PI. 1:320. 1798. 



Dilepyrum minutifloriim Michx. Fl. Bor. Am. 1:40. 1803. 



Muhlenbergia diffusa vSchreber, Gram. 2:143, 18 10. 



Muhlenbergia diffusa Schreb., Bush in Flora of Jackson County, 

 Missouri, No. 864, 1885; Tracy in Flora of Missouri, No 1641, 

 1886; Eggert in Catalogue of Plants of Saint Louis, Missouri, 1891 ; 

 Daniels in Flora of Columbia, Missouri, No. 75, 1907; Palmer in 



