6 



Plants belonging to this species have nsually been referred to Poa cuspidata 

 Vasey, but the type of that species belongs to Poa tvheeleri Vasey, from which 

 Poa epilis differ in its smooth sheaths, contracted panicles and abundantly 

 produced intravaginal shoots. 



Poa epilis ranges from central Colorado to northeast Wyoming and central 

 Montana, and occurs in the mountains at rather high altitudes. 



11. pOA INCURVA Scribn. & Williams, sp. nov. 



A slender, closely caespitose perennial about 3 dm. high, from strong fibrous roots, 

 with purplish fiexuous stems, rather rigid flexuously recurved leaves and 

 small, purplish panicles 2-4 cm. long. Culm smooth. Culm-leaves about 2, 

 smooth below, minutely hispidulous above and at the acute apex, convolute, 

 1-3 cm. long ; sheaths smooth, striate, shorter than the internodes ; ligule acute, 

 often irregularly fimbriate, 1-2 mm. long. Leaves of the sterile shoots much 

 longer than those of the culm, recurved-flexuous, otherwise similar; basal 

 sheaths persistent. Panicle few-flowered, fiexuous, the branches mostly soli- 

 tary, minutely scabrous, flower-bearing at the outer extremities. Spikelets 

 compressed, purplish, loosely 2-8-flowered, about 5 mm. long: empty glumes 

 unequal, the lower oblong-lanceolate, subacute, indistinctly 3-nerved, slightly 

 more than 2 mm. long, the upper broadly ovate, obtuse or subacute, dis- 

 tinctly 3-nerved, usually a little more than 3 mm. long; flowering glume 

 rounded on the back, indistinctly 5-nerved, ovate, obtuse or subacute, smooth- 

 ish above, densely pubescent below, the pubescence strongest on the middle 

 and marginal nerves, purple on the back, rather broadly scarious-margined 

 above, about 4 mm. long ; palet nearly or quite eqxialing the flowering glumes, 

 strongly 2-keeled, ciliate on the keels, apex bidentate. 



Type specimen No. 1989, C. V. Piper, Morain of Duckaloose Glacier, Olympic 

 Mountains, Washington, August, 1895. Altitude, 2,100 meters. 



Allied to Poa. sandbergii Vasey but distinguished by its flexuous stems, smaller 

 spikelets, and smoother, convolute, recurved-flexuous leaves. 



12. POA INVAGINATA Scribn. & Williams, sp. nov. 



A smooth, caespitose erect or somewhat decumbent perennial, aboiit 4 dm. high, 

 wdth numerous intravaginal shoots, marcescent sheaths and pale, open pan- 

 icles 10-12 cm. long. Leaves mostly flat, rather narrow, acute, smooth or 

 the margins minutely hispidulous near the base; sheaths smooth, striate; 

 ligule acute, decurrent, 4-5 mm. long, alike on leaves of both culms and 

 sterile shoots. Panicle subpyramidal to oblong, the branches usually in 

 threes or fives, filiform, flextious, scabrous, flower-bearing along the upper 

 half, the longer ones seldom exceeding 5 cm. in length; spikelets compressed, 

 lanceolate, rather loosely 2-4-flowered, 6-7 mm. long ; empty glumes 3-nerved, 

 narrowly oblong to oblong-ovate, obtuse or subacute, the lower 3-4 mm. , 

 the upper 4-5 mm. long; flowering glumes keeled, oblong ovate, obtuse or 

 subacute, 5-nerved, minutely scabroiis above, pubescent below on the nerves 

 and sometimes sparsely pubescent between them, 4-5 mm. long; palet 

 shorter than the flowering glume, ciliate on the keels, apex erose-dentate. 



Type specimen in Herb. Scribner, No. 20, Calif. Acad. Sciences, collected at 

 "Summit Camp, Sierra Nevada," July 10, 1870. 



It has been collected by C. F. Sonne at Dormer Lake, Calif., July 4, 1892 (No. 17) 

 and at Mt. Stanford, Calif., August, 1888 (No. 24), and also by W. N. Suks- 

 dorf at Mitchells Point, Wasco Co., Oregon, May, 1884 (No. 107a). 



This species has been confused with Poa gracillima Vasey and Poa cusickii Vasey 

 but may be easily distinguished from the former by its coarser habit, flat 

 leaves, larger and more abundantly flowered panicle, larger spikelets and 

 longer, more conspicuously nerved flowering glumes, and from the latter by 

 its broader, flat leaves and pubescent flowering glumes. 



I 



