No. 83. 

 POA PURPURASCENS Yasey, Bot. Gaz. vi. 297 (1881). 



Plant perennial, tufted or cespitose, from a strong rootstock. 



Culms erect, wiry, smooth or slightly seabrid, usually naked above the middle, 10 to 

 15 inches tall. 



Leaves of sterile shoots numerous, with short, narrow sheaths and closely involute, 

 smooth or seabrid, erect blades less than 1 line wide and 4 to inches long: leaves of the 

 culm 2 or 3; sheaths striate, smooth, the lower ones short but exceeding the inter- 

 nodes, the upper one extending half the length of the culm ; blades wider and less 

 involute than those of the base or often flat, 1 to 2 inches long; ligule obtuse, 1 line 

 long or less or often nearly obsolete. 



Inflorescence a rather closely flowered, oblong panicle 1 to 3 inches long ; rays hispid, 

 2 to 4 at each of the 5 to 7 nodes, 1 inch long or less, nearly erect or somewhat spread- 

 ing, subdivided and spikelet-bearing near the extremities or above the middle. 



Spilcelets rather turgid, 3- to 5-flowered, 2J to 3 lines long; empty glumes ovate, 

 acute or subobtuse, smooth, 1-nerved or obscurely 3-nerved, 1 J to 2 lines long, shorter 

 than the lower florets ; floral glume lance-ovate, acute or obtuse, sometimes slightly 

 cuspidate, minutely seabrid throughout, hispid-ciliate on the keel, narrowly scarious- 

 margined above, 5-nerved, 2£ to 3 lines long ; palet oblong, obtuse, ciliate on the 2 

 keels, 2 lines long; grain oblong, greenish yellow, nearly opaque, 1 line long; inter- 

 node of rachilla slender, nearly smooth, about % line long, the upper one bearing a 

 minute rudiment. 



Plate LXXXIII; a, spikelet; &, floret. 



Central California to British Columbia and eastward to Colorado. Iu is somewhat 

 variable, as any Poa must be with such a range. The first description was based on a 

 series of specimens which were uniformly purple in the inflorescence, but other forms 

 differing only in this one respect cannot be excluded. 



