Piper New and Interesting American Grasses. 149 



with a stout divergent scabrous awn of equal length ; palet oblong-linear, 

 obtuse, shorter than the body of the flowering glume, the nerves strongly 

 scabrous ciliate, the sides less than one-half as broad as the internerve. 



Type specimen collected by Williams and Griffiths, No. 140, on the North 

 Fork of Clear Creek, Wyoming, altitude 2,600 meters. Other specimens 

 are referred here as follows : 



Wyoming: Near Beulah, Griffiths 412; Inyan Kara, Griffiths 641. 



North Dakota : Dickinson, M. A. Brannon 123 ; Broncho, L. R. Waldron 

 2232. 



The species is near A. alMcans Scribn. & Smith, but is readily separable 

 by its nearly smooth flowering glume. 



Agropyron sitanioides J. G. Smith sp. nov. 



" Culms erect or ascending, 20 to 30 cm. high, their bases clothed with 

 tumid leaf sheaths ; innovations <> to jj the length of the culm, stout, rigid, 

 internodes terete, glabrous. Sheaths closely enveloping the internodes 

 scarious along the margins, glabrous; ligule obsolete, blades rigid, erect, 

 involute, filiform, sharply-pointed, scabrous on the back, strongly nerved 

 and scabrous above and on the margins. Spike rigid, erect, long-exserted, 

 5 to 8 cm. long. Spikelets strict, erect, few-flowered. Internodes of the 

 rachilla 1 mm. long, hispid. Empty glumes subulate, entire or bifid, 2- 

 nerved, very scabrous along the nerves, with a stout, scabrous, ascending 

 awn 3 to 4 cm. long; flowering glumes coriaceous, lanceolate, applanate on 

 the back, 8 to 9 mm. long, nearly 2 mm. wide, scabrous, with a stout, ascend 

 ing or spreading awn about 5 cm. long arising from between two short 

 teeth ; palet shorter than the flowering glume, obtuse, callus hispid. 

 Internodes of the rachis compressed, scabrous along the margins, somewhat 

 dilated above, about 4 to 5 mm. long. 



"Type collected by David Griffiths, No. 735, Rapid City, South Dakota, 

 August 28, 1897. Growing on dry knolls. 



This species is doubtfully referred to Agropyron. It agrees with species of 

 Sitanion in having the rachis of the spike subarticulate at maturity ; the 

 empty glumes bifid, and the flowering glume trifid. It is like Elymus in 

 the lanceolate empty glumes, scabrous callus of the flowering glume, and 

 scabrous internodes of the rachilla, but the solitary spikelets and opposite 

 empty glumes enclosing the base of the spikelet between them denote a 

 closer generic affinity with Agropyron, although it is not closely related to 

 any of the American species." 



Agropyron flexuosum comb. nov. 

 SUanion flejcnomm Piper, Erythea 7 : 10. (1899). 



Repeated field observations of this species since its publication, together 

 with the careful study of a large series of specimens, demonstrate that it 

 must be considered a close relative of Agropyron spicatum (Pursh). It is 

 not at all uncommon to find the spikelets at some of the nodes of the 

 rachis in this last- species, for instance in Cusick's No. 1914, from eastern 



