I20 MEMOIRS OF THE NEW YORK BOTANICAL GARDEN. 



mm. long at maturity, clothed with appressed or ascending somewhat 

 silky hairs ; segments spatulate, the inner narrower than the outer, all 

 obtuse, slightly crisped in age ; filaments villous below the middle ; 

 achenes fully 2 mm. long, sparingly villous at the tip or glabrate. 



Eriogonum ^olyphylliini is related to E. fiaviiin. It is much 

 smaller than any of the dwarf states of the latter species. The pu- 

 bescence is more woolly and less floccose than that of E.Jfavnni and 

 is less copious on the calyx. The newly described species can be 

 separated from its relative by the short scapes, the sessile or nearly 

 sessile involucres and the smaller calyx which is less manifestly 

 stipitate at thq base. It grows in rocky or gravelh' exposed situa- 

 tions at an altitude of 2700 m. 



Montana: Old Hollowtop, Pon}- Mts., July 9, 1897, Rydbcrg it 

 Bcssey, jj2j. 



* Eriogonum Piperi Greene, Pittonia, 3: 263. 



Like E. faviiiu but differs in the thinner leaves, more villous pu- 

 bescence, and long-acuminate base of the perianth. Dry open \al- 

 leys in the mountains, at an altitude of 2000-2500 m. 



Yellowstone Park : Upper Geyser Basin, 1884, Tzveedv, ly; 

 Upper Geyser Basin, Aug. 8, 1897, Rydberg & Bessey, 5329: Lone 

 Star Geyser Basin, 3328 ; Upper Falls, Aug. 14, 332/. 



Montana: Birch Creek, 1883, Canbv, 2ji; Jocko River, 27^. 



In subalpine and exposed stations it becomes low (5-10 cm. high) 

 and more tufted, as for example the following specimens : 



Montana : Spanish Basin, 1896, Elodinaii,j'/S and j8i ; Elk Mts., 

 37g; Haystack Peak, 1887, E. Tzcccdy, loi; Madison Co., M?-s. 

 L. A. Fitch; Silver Bow Co., 1888, Tweedy, 108; Old Hollow- 

 top, Pony Mts., July 7, 1897, Rxdbei'g & Bessey, 3326. 



Yellowstone Park : 1883, Mary Compton. 



Eriogonum caespitosum Nutt. Journ. Acad. Phila. 7: 50 [Man. R. 

 M. 314; Bot. Cal. 2: 19; Wats. Rev. 256]. 

 Dry hills at an altitude of 1000-2500 m. 

 Montana: Cottonwood Creek, 1885, Elodman, 2y/. 

 Yellowstone Park : Sepulcher Mt., 1885, Tzt'ecdy, y/j. 



* Eriogonum andinum Nutt. Journ. Acad. Phila. II., i : 160. 



Similar to E. caespitosum in habit, but with smaller flowers and 

 spatulate leaves. Dry benches at an altitude of 1500-2000 m. 



Montana: Beaver Head Co., 1888,/^. Tiveedx, 106; Virginia 

 City, 1871, Robert Adams (Hayden Surv.). 



