MEMOIRS OF THE NEW YORK BOTANICAL GARDEN. 121 



Eriogonum sphaerocephalum Dougl. ; Benth. Trans. Lin. Soc. 17: 

 407 [Bot. Cal. 2: 19; Man. R. M. 314; Wats. Rev. 257]. 

 Dry benches and rock}' hills up to an altitude of 500 m. 

 Montana: Flathead Region, 1883, H. B. Ayrcs. 



Eriogonum umbellatum Torr. Ann. Lye. N. Y. 2: 241 [Man. R. 



M. 313; Bot. Cal. 2: 19: Wats. Rev. 257]. 



Dry hills at an altitude of 1000-2500 m. 



Montana: Little Blackfoot River, /. G. Cooper- Grasshopper 

 Valley, 1880, Watson. 



Yellowstone Park : Upper Geyser Basin, 1884, Tzvccdv, 2 

 and 20; 1897, Rydberg i&: Bcsscv, Jjjo. 



* Eriogonum latum Small. 



Perennial, shrubby at the base. Stems copiously branching, 

 spreading and forming large mats 3-5 dm. broad ; leaves clustered at 

 the bases of the scapes or at the ends of the branchlets, rather numer- 

 ous ; blades oblong, oval or elliptic, sometimes broadest slightly below 

 or above the middle, obtuse, felt3--pubescent or slightly floccose be- 

 neath, glabrous or glabrate above, cuneately narrowed at the base ; 

 petioles as long as the blades or shorter ; scapes erect or ascending, 

 2 dm. long, more or less floccose, topped by an umbel with 3-8 

 rays ; bracts mainly oblong or spatulale, reflexed in age ; rays of the 

 umbels stout, 2-5 cm. long ; involucres several ribbed ; segments 

 usually 6-10, unequal, reflexed, mostly longer than the tube ; calices 

 very numerous in dense heads 2-2.5 ^^' ^^ diameter, light yellower 

 yellowish green, or purplish tinged in age, becoming 8-9 mm. long, 

 stipe-like at the base ; outer segments oblong above the cuneate base, 

 rounded at the apex ; inner segments spatulate ; filaments pubescent 

 to above the middle ; ovary sparingly villous at the top ; achene 

 glabrous or nearly so. 



Eriogo7iian latum is related to both E. umhellatum and E. siibal- 

 piniivi. It is more robust than either and also more woody. It may 

 easil}^ be distinguished by the calices which are about twice as large 

 as those of both its relatives. 



It grows in dr}^ gravelly soil at an altitude of 500-2500 m. 



Montana: Cottonw^ood Creek, 1896, Flodman ; Pony Mts., July 

 5, 1897, Rydberg & Bessey, 5332; Cliff Lake, July 27, 3333. 



Washington: Tumwater Caiion, 1893, Sandberg & Lciberg, 

 321. 



Idaho: Blackfoot, 1893, Palmer, 281; Mt. Chauvet, July 29, 

 1897, Rydberg & Bessey, 3331. 



