404 IVIEMOIRS OF THE NEW YORK BOTANICAL GARDEN. 



*Erigeron gracilis. 



Perennial, with a branched rootstock ; stem simple, ascending at the 

 base, slender, strigose, about 1.5 dm. high, monocephalous ; basal 

 leaves spatulate to linear-oblanceolate, thin, slightly strigose, entire, 

 2-4 cm. long; stem leaves narrowly linear, acuminate, the upper 

 reduced; head about 6 mm. high, 10-12 mm. in diameter; bracts 

 narrowly linear, tinged with purple, strigose, only slightly imbricated ; 

 rays about 50, slender, light purplish, 7-10 mm. long. 



This has been labeled E. ochroleucus, but is easily distinguished by 

 the slender branched rootstock, slender simple stems, thin leaves aud 

 longer purplish rays. It grows in low meadows, at an altitude of 

 about 2500 m. 



Yellowstone Park: Slough Creek, 1885, Tzveedy, ■/02 (type); 

 Yancy's 1899, Aven JVchon, 372 j. 



* Erigeron argentatus Gray, Proc. Am. Acad. 8: 649 [Syn. Fl. i" r 



212] . 



Somewhat like E. canus, but taller, with larger heads and finer 

 white pubescence. Dry hills, at an altitude of 2000 m. 



Montana: Jack Creek, July 19, 1897, Rydberg & Besscy, 308 j ; 

 Lima, 1895, Rydbcrg, 2827. 



* Erigeron peucephyllus Gray, Proc. Am. Acad. 16: 89 [Syn. FL 



I-: 213]. 



Somewhat like E. ochroleucus but with unequal imbricated bracts, 

 more lax leaves, and cinereous, not hirsute pubescence. On rocky 

 hills and meadows, at an altitude of 2000-2500 m. 



Montana: Bear Gulch, 1887, Tzvecdy, j6j. 



Erigeron Eatonii Gray, Proc. Am. Acad. 16: 91 [Syn. Fl. i- : 214; 



Man. R. M. 172] . 



On high mountain tops, at an altitude of 2500-3000 m. 



Montana AND Idaho : Mt. Chauvet, July 29, y^c)"], Rydbcrg & 

 Besscy, J077. 



* Erigeron Parryi Canby & Rose, Bot. Gaz. 15: 65. 



Like E. radicatiis in habit, but with hirsute leaves, a double pap- 

 pus, and a head more resembling a depauperate E. cacspilostis. 

 Grows in dry soil. 



Montana: Grasshopper Creek, 1888, Tweedy, /j. 

 Erigeron caespitosus Nutt. Trans. Am. Phil. Soc. (II.) 7: 307 [111. 



Fl. 3: 386; Syn. Fl. i- : 214; Bot. Cal. i: 327; Man. R. M. 



172]. 



