66 PAMCACK.l':. 



bent uwn 7-15 mm. long. Pedicels shorter tlnm tlie sterile spike- 

 lets, which they betir; iirst irltime lliittened. ovjite-laiu'eolate. (!-S 

 .11111. long. 7-ncrve(l, margins involute: second ;5-nerved. 5 mm. long; 

 third and fourth as long as the second, and hyaline. Stamens 3. 



From liocky ^Mountains and east to the Atlantic; found in good 

 soil or in poor and dry soils; also abundant on the prairies, where ifc 

 is the leading grass for hay and very prominent for grazing. 



In Coult. Hot. (iaz. 'M)-l (ISSS) A. A. C'rozier states that in 

 Iowa the plants are largely di(eoious. The fertile plants are smaller 

 and darker in color than the others. 



^[exico, rriiif/le 4294; D. C, McCarthy; Mich., Ural G. 

 Kansas 7. 



Var. pycnanthus Hack. D. C. Monog. Phan. : 44.3 (ISS!)). 

 Silky hairs larger and tawny; first glume of pedicellate spikelet .5 

 mm. long, .')-nerved. Mex., Urandv(jee 47, teste E. Ilackel iu 

 herb. iScrihner. 



24. A. Wrightii Hack. Flora. (58 : TOO (188,5). 



Plant smooth, glaucous, 100-120 cm. high, culms usually sim- 

 ple above. Leaf-blades 20-30 cm. long, 5 mm. wide, the upjier 

 ones about 10 cm. long, short hairs at the nodes and ligule; the 

 latter 1 mm. long. Si)ikes 4-0, digitate. 4-(! cm. long; rachis and 

 pedicels well clothed with hairs which are shorter than the spike- 

 lets. On sessile spikelots first glume elliptical-lanceolate, 0-7 mm. 

 long, tlattened on the back, which contains a round pit one-third 

 the way from the tip, 11-nerved, margins involute; second ovate- 

 acute, membranous, keeled, 3-.'erved; third and fourth hyaline, 

 the latter bearing a twisted awn 2-3 mm. long. On the pedicellate 

 spikelet first glume 7 mm. long, ovate-lanceolate, rounded on the 

 back. 13-nerved, margins involute; second same shape aud nearly as 

 large, 4-5-nerved; third hyaline. 



N. Mex.. 1IW//7// 2104; Mex., Priin/Ie liOO. 



New Mexico to Arizona and Mexico. 



25. A. saccharoides Sw., Fl. Tnd. Occ. 1:20 (1707). 



Culms stout or slender, 80-120 cm. high, hairy at the nodes, 

 branching below. Sheaths terete, ribbed, glaucous, glabrous; 

 ligule short, hairy; blades 8-25 cm. long. 4-7 mm. wide. Spike- 



