64 PANKACE.E. 



of peduncle, racliis, and iK'dici'ls clotlit'd witli soft luiirs lU'iirly 1 

 cm. long. Sessile spikelet lineiir-liuiceolate. 4 mm. long. Spikclet 

 like that of J. Virgittivux L. Pedicel 4 mm. long, bearing a very 

 short rudimentary spikelet. It has the general appearance of 

 A. {arfjeuteuH Ell.) (irgi/rcii.s Schultz, Curtiss IMioT. 



The plant seen is owned by F. L. Hcribner, Coll. by A. 1*. 

 Garber in 1877 in Miami, Fla., distributed as A. aryoifeus Ell. 

 Marked •• teste E. Hackel.'' 



Florida, (Jiii'tiss 30.'39, distributed as A. macronruH !Michx. 

 var. viridis Chapm. ined. 



It is well branched, and too near A. ViryininiH L. Perhaps 

 my s[)ecimens are not genuine. 



21. A. Hallii Hack. 8itzb. Akad. Wien. 89 : 127 (1884). 



Plant glaucous, smooth, exce])ting the margins of the blades. 

 Culms rather stout. 80-120 cm. high, usually branching once or 

 more near the top. Tjigule 2-.'5 mm. long; blades of the culm 15 

 cm. long, 4 mm. wide, the upper reduced to mere ]ioints. Spikes 

 2, at the apex of the cidm and branches. o-O em. long, protruding a 

 little aI)ove the leaves; rachis and pedicels pubescent on the edges, 

 the hairs shorter than the s})ikelets. First glume of sessile spikelet 

 firm, lanceolate, 11 mm. long, a vertical groove on the back, mar- 

 gins involute, (!-nervcd; second curved towards the flower, ovate- 

 lanceolate when spread, 10 mm. long, compressed-keeled, a faint 

 nerve on each margin; third shorter, hyaline, fourth hyaline, bifid, 

 bearing a twisted awn over 1 cm. long; palea hyaline, 6 mm. long, 

 1.5 mm. wide. Lodicules truncate, 1 mm. long. The first glume 

 of the pedicellate spikelets lanceolate, scabrous, margins involute, 10 

 mm. long, 0-nerved; second a little shorter, 3-nerved; third and 

 fourth hyaline, containing rudiments of stamens and pistils. 



Colorado, Vaspi/ ; Texas, XeriJIej/. 



Growing from Kansas to Arizona. 



Var. flaveolus Hack. Joints of the spikes with yellow hairs; 

 spikelets 8 mm. long, first and second glumes pilose on the back 

 or outside; the awn of the fourth 2-5 nmi. long, scarcely extend- 

 ing above the hairs of the other glumes. B. Hall 651; Barbottr in 

 1803; Texas, Nealleij. 



