No. 55. 



CALAMAGROSTIS ARCTICA Vasey, sp. nov. 



Plant perennial, from a creeping rootstock. 



Culms decumbent at base, smooth, 5 to 10 inches tall, covered below with persist- 

 ent, scarious. sheaths. 



Leaves from the base, numerous, flat, smooth, 2 lines wide, half as long as the 

 culm; but 1 or 2 above the decumbent base, these with rather long sheaths loose 

 above, half open at the throat, smooth and thin; the blades erect, flat, or folded, about 

 1 inch long; ligule nearly acute, about 1£ lines long. 



Inflorescence, a dense, short, spicate panicle, 1 inch long and £ inch wide,,rays ^ 

 inch long, in glomerate clusters. 



Spilcelets 1-flowered, 2 to 2J lines long; empty glumes narrowly lance-ovate, at- 

 tenuate-pointed, hispid on the keels and minutely scabrid throughout, purple below, 

 the first 1-nerved and slightly longer, the second 3-nerved, 2 to 2£ lines long; floral 

 glume oblong, acutely 4-toothed at the apex, smooth, purple above, 4-nerved, 2 lines 

 long; awn arising near the base, 2\ to 3 lines long, exserted beyond the empty glumes ; 

 palet oblong, 2-toothed at the apex, nearly smooth on the keels, about equaling its 

 glume; hairs of the callus and sterile pedicel one fourth as long as the floret. 



Plate LV; «, spikelet dissected, showing all the parts somewhat spread; b, floral 

 glume, do -sal view. 



St. Paul Island, Bering Sea. Collected by J. M. Macoun, 1891. 





