57 



divergent, 1.5 to 2 cm. long. First llowering glume about 1 cm. long, smooth 

 or slightly scabrous near the apex, rather broadly lanceolate and gradually 

 tapering into a slander, llcxuous, more or less divergent awn, 2 to 2.5 cm. long. 

 Palea as long as its glume, tinely aculeolate-scabrous on the keels. Apex 

 rounded-obtuse or truncate and pubescent. 

 Among bowlders and rocky crevices on the summit ol Mount Chapaca, altit\ule 1,900 

 meters (No. 554, A. D. E. Elmer, August, 18!)7). Distributed as Ji/ropiiron saxi- 

 cohim. This grass was at tirst taken to be a species of Jgropyroii, but an exami- 

 nation of further material determines its ]>osition as an Kljimiis. In many of 

 the spikes the spikelets are all scditary, but the position ol' the lirst lloweiing 

 glume in being slightly turned to one side in its relation to the nuiiu axis is a 

 character of the genus ElijmiiK, and there are fre([uently entire spikes where the 

 spikelets are all in pairs as in the typical species of the genus. The soft, ho.-iry 

 pubescence and slender divergent awns aiv the most striking characters of this 

 species. 



ELYMUS CILIATUS Scribn., sp. n. (PI. XVI.) 



A rather slender, erect perennial about 7 dm. high with soft, flat leaves and slender, 

 nodding spikes, 7 to 12 cm. long. Culms very smooth. Sheaths smooth, striate. 

 Ligule less than 1 mm.' long. Leaf-blades linear, lanceolate, 12 to 18 cm. long, 

 nearly 1 cm. broad, scabrous on both sides and especially on the margins. Axis 

 of the panicle strongly scabrous. Spikelets about 1.5 cm. long, exclusive of 

 the awn, 2- to 3-tlowered. Empty glumes lanceolate, 3-uei'ved, about 8 mm. long 

 exclusive of the awn, which is 3 to 4 mm. long; the outer pair of glumes ciliate 

 near the apex, the inner pair usually naked. The first flowering glume about 1 

 cm. long, 5-nerved, nerves prominent near the base, ciliate-pubesceut along the 

 margins, especially near the apex. Awns straight or somewhat iiexuous, 2 to 2.5 

 cm. long. Palea al>out as long as the glume, finely aculeolate-scabrous along 

 the margins near the 2-toothed apex. 



Common in wet places, Sitka, Alaska (No. 210, Walter Evans, .June, 1897; No. 1724 

 Howell). This species is related to Elymus sibiricus, from which it is distin- 

 guished by its longer and broader outer glumes and the ciliate margins of the 

 flowering glumes. This latter character serves to distinguish this species from 

 all others with which the writer is acquainted. 



ELYMUS SIMPLEX Scribn. &, Williams, sp. n. (PI. XVII.) 



A rigid species, 3 to 4 dm. high, the erect stems from strong, creeping rootstocks, 

 with flat, pungently-pointed rigid leaves and densely flowered sjiikes 5 to 8 cm. 

 long. Culms branching at the very base, growing in thin, scattered tufts. 

 Lower sheaths crowded, exceeding the internodes, gl.abrous and smooth. Ligule 

 very short, auricled. Leaf-blades 4 to 10 mm. long, 3 to (5 mm. broad, becoming 

 involute Avhen dry, smooth the lower surface strigose-scabrous above, the 

 very sharp, involute tips straw-colored. Axis of the panicle scabrous, strongly 

 flattened and scabrous on the edges, not readily breaking up. Spikes solitary 

 or in pairs, sessile and shortly pedicellate, slightly compressed, usually crowded, 

 rarely remote, about 1.5 cm. long, 5- to 7- (or more in var. luxurians) llowered. 

 Empty glumes slightly unequal, very rigid, the longer one about 1 cm. in length, 

 narrowly lanceolate, very rigid and long subulate-])oiuted. i'^irst flowering 

 glume about 7 niiu. long, rounded on the back, smooth, mor(>. or less glaucous, 

 extending into a rigid awn, 5 to (i mm. long. Palea deeply sulcato toward the 

 base, about as long as its glume, aculeolate-scabrous on the strong keels, except 

 ing near the base. Apex narrow, minutely 2-toothed, very minutely scabrous 

 or snbpubescent on the back. 



Type specimen is represented by No. 2.331, Thomas A. Williams, collected on banks 

 of Green Eiver, Wyoming, .July 8, 1897, altitude 1,800 meters. No. 23()(i of the 

 same collection belongs here. This was collected on edges of ponds and along 

 river bottoms in the same vicinity, gmwing with DisticIiUs spirala. 



