49 



aud with the branches scabrous. Spikeh'ts 2 to 2.3 miii. h)n,!;-. Eiiipty uliimes 

 less than 1 mm. in leugth, broadly obtuse or trimcate and occasioually miuutely 

 erose-dentate, miuutely scabrous ou tlie back above. Flowering glumes 3-nerved, 

 mucrouate-pointed or subaristate, scabrous above. Palea a little shorter than 

 the glume. 

 Type specimen 2411, P. A. Rydberg, Georgetown, Colo., August 19, 1895. II. N. Pat- 

 terson collected the same form in the same region in 1885. A rigid and appar- 

 ently a perennial form of this species was collected by C. (J. Pringlo near 

 Summit Valley in the Sierra Nevada Mountains, California, September 19, 1882, 

 and distributed as Sjyoroboluts yra- 

 ciilimus, with which the species is 

 most closely allied. It is distin- 

 guished fronr^S'. (jracilUmns by its , . 

 broader, more rigid leaves, more I / 

 scabrous panicle-branches, and \ 

 generally stouter habit of growth. 

 It has heretofore been referred 

 to Sporoholus ijracillimua. No. 1041, 

 C. L. Shear, from Twin Lakes, 

 Colo., August 23, 1891), belongs to 

 Sjjorobolus simplex. 



AGROSTIS PALUDOSA Scribn., 

 sp. n. (Fig. 7.) 



A low, densely ca-spitose perennial, 10 



to 15 cm. high, with soft, narrow 



leaves; narrow, rather densely 



flowered panicles, 3 to 5 cm. long. 



Sheaths smooth, the lower thin 



and somewhat scarious. Ligule 



elongated, about 2 mm. long. 



Leaf-blade soft and flaccid, at 



least the lower ones, minutely 



scabrous on the margins, other- 

 wise smooth. Panicle- branches 



scabrous. Sjiikelets 3 mm. long. 



Enii>ty glumes ovate, lanceolate, 



acute, equal, subciliate, scabrous 



on tlie keel excepting near the 



base. Flowering glume nearly 3 



mm. long, rather broadly obtuse, 



very miuutely punctate-scabrous 



on the back excepting near the 



tix), awnless. Palea about 0.5 



nun. long, hyaline. Callus very 



sliortly 1)arbate on the sides. 

 Blanc Sablou, Labrador (llev. A. Waghorne, September 25, 1893). Apparently a 



well-marked species, allied to Agrostix rarians, but with much larger spikelcts. 



TRISETUM ARGENTEUM Scrilm., sp. n. (Fig, 8.) 



A slender, erect perennial with suu)oth culms, 5 to 7 dm. high, very minutely sca- 

 brous sheaths and leaves, aud narrow, silvery -gray or purplish panicles, 10 to 

 20 cm. long. Culuis minutely pul)e8(;eut at the nodes aud otherwise, glabrous. 

 Sheaths minutely pubescent, especially those of the sterile shoots. Ligule 

 about 2 mm. long with a broad, erose or lacerate apex. Leaf-blades linear, 10 to 

 20101— No. 11 4 



Fig. G.—Spoyuboliin simplex Scribn. : a, empty 

 lumes; 6, .spikelet, empty glumes removed ; c, grain. 



