36 



on open grounds grazed down with the other grasses. Head of North Vtrniilion 



Creek, July 20 (3792) ; Evauston, July 28 (3851) ; Battle Lake, August 16 (4021). 



Agrostis tenuis Vasey (Slknder Haiu-gkass).— Resembling the preceding, but 



smaller, the panicle and its i)edicels shorter and less spreading. Collected but 



once, in ground then fairly dry, hut probably boggy earlier in the season. 



Low (6 to 12 inches high), and in small quantity. Battle Lake, August 1G(4014). 



Agrostis huniilis Vasey (fig. 9).— A bunch grass of very small proportion, only 3 to 



5 inches high; seemingly very rare; only one small bunch secured on an alpine 



summit near a snowbank. Battle Lake Mountain, August 17 (4070). 



Calamagrostis hyperborea americaua Kearn. (Sano-grass; Ykllowtoi-).— A tall 



fine-looking grass, with close 

 cylindrical heads, often 3 to 4 

 feet high. In this range it 

 seems to be found in a-bun- 

 dance in wet draws and on 

 banks where seepage water is 

 abundant. It often forms a 

 close, even growth, but as it 

 requires so much water it can 

 not be utilized, except on tlie 

 wettest ground, as a meadow 

 grass. Pine Bluti's, July 6 

 (3632); North Fork A'ermil ion 

 Creek, July 19 (3772); Gran- 

 ger, July 30 (3884); "Woods 

 Lauding, August 7 (3902); 

 Medicine Bow Kiver, Augiist 

 21 (4089). 

 Calamagrostis cauadenfis (Mx.) 

 Beauv. ( Bu'e-joixt grass). — 

 Stems and leaves stouter than 

 in the preceding, heads close 

 and full, 2 to 3 feet high ; in- 

 frequent, usually in wet places 

 or on creek banks. Head of 

 Pole Creek. .Inly 22 (3437). 

 Calamagrostis canadensis acu- 

 minata Vasey (Mountain 

 Blue-joint). — Much resem- 

 bling the preceding in general 

 appearance; in age the pani- 

 cle is loose and sitreading. It 

 is the commoner form of this 

 range, occurring both in t>pen 

 and in partially shaded 

 ground. Its luxuriant growth 

 and am)>lc leaves suggests 

 that it may be valuabic under 

 cultivation. In one mountain 

 locality it formed a luxuriant and continuous growth among the fallen timber. 

 Johnsons Kanch, August 9 (3905); Woods Creek, August 10 (3946); Battle Lake, 

 August 16 (4018). 

 Calamagrostis moutanensis Scribn. (Montana Bluk-.ioint).— A small erect form, 

 with close cylindrical heads, rarely more than a foot high. It occurs on dry or 

 even on rocky slojjes, and on the drier parts of th«' bottom lands as scattering spec- 

 imens or irregular i)atches of various sizes. It must be considered as a pasture 

 grass of some value. Horse Creek, July 13 (3381) ; Big Creek, August 11 (3970). 



Fig. 7.— Kouj;h-leal'ed Salt-};ni88 (Spvrobulus asjierif alius) 

 a, empty glumes; b, floret; c, fjiryopsis. 



