6 



POA EATONI S. Watson, Bot. 40th Parallel, p. 386, 1871. 



An erect, caespitose perennial 4-G dm. high, from short rhizomes, with rough, 

 more or less glaucous leaves and rather open, oblong, or somewhat ovate 

 panicle, 7 or 8 cm. long. Culm smooth, more or less roughened immediately 

 below the panicle, composed of two or three internodes, all biit the lowest 

 exceeding the sheath, the upper one long and miich exserted. Leaf -blades 

 flat or becoming conduplicate, scabrous below, and rough-hispid above; 

 those of the basal leaves spreading, 1-2 dm. long, those of the cauline leaves 

 seldom over 2 cm. long, the upper one often reduced to a mucro. Ligule 

 short, with a rounded or truncate apex, that of the leaves of the sterile 

 shoots reduced to a narrow band or fringe. Sheaths striate, the basal ones 

 persistent. Panicle branches scabroiis, erect or ascending, seldom more 

 than 3 cm. long, flower-bearing along the upper half ; spikelets compressed, 

 oblong, rather obtuse, 5-9-flowered, 7-10 mm. long, about 3 mm. broad. 

 Empty glumes subequal, acute, or subacuminate, the lower 1-, the upper 

 imperfectly 3-nerved, hispid on the keels ^Hl the length of the adjacent 

 flowering glume. Flowering glumes strongly keeled, the keels and lateral 

 nerves thickly pubescent below, hispid above, smooth between the nerves, 

 4-5 mm. long, the intermediate nerves obsolete. 



Very closely allied to Poa fencUerimia but possibly distinct through its oblong, 

 usually more numerously-flowered spikelets and shorter, broader, spreading 

 leaves which, though rough, are not pubescent on the upper surface. It is 

 possibly more strongly rhizomatous but this can only be determined by 

 studies in the field. No specimens have been seen that can be referred to 

 this species except those from the original collection by D. C. Eaton at Cot- 

 tonwood Canyon, Wahsatch Mountains, Utah, where the plants grew in dry 

 rocky soil at an altitude of 2,000 meters. Most of the material that has been 

 placed by botanists under this species is true Poa fendleriana. Prof. J. 

 Macomi has collected a plant in British Columbia (No. 58, Spencers Bridge, 

 1889; and 91, and 93, Valley of Eraser River, 1875), which has much the 

 habit of P. eatoni to which it has been referred btit it has the longer leaves 

 (more or less hispid-pubescent above) and ovate to ovate-lanceolate spikelets 

 of P. fendleriana and seems to be an intermediate form. It is not improbable 

 that further study will result in the suppression of Watson's species. 



Note.— In Circular 9, Div. Agrost., p. 3, the name Poa plaid folia was applied 

 to a species of the Rocky Mountain region, but since this combination has already 

 been used by Dr. O. Kuntze (Revis. 3:, pt. 3, sec. 2, p. 366, 1898) for a South 

 American plant, a new name is necessary for our species. It may be called Poa 

 glaiicifolia Scribn. and Williams. 



Thomas A. Williams, 



Assistant Agrostologist. 

 Approved : 



James Wilson, 



Secretary of Agriculture. 



