POLYGONE^. 45 



4. E R10GONUM, Michaux. Annual, perennial or suffrutescent plants 

 with radical or alternate or verticillate exstipulate leaves and a greatly 

 diversified inflorescence of involucrate, mostly small and dense primary 

 flower-clusters. Involucre campanulate, turbinate or oblong, 48- 

 toothed or -lobed without awns; the pedicels few or many, more or less 

 exserted, subtended by scarious and narrow or quite setaceous bractlets. 

 Perianth 6-cleft or -parted, colored, enclosing the achene. Stamens 9, 

 upon the base of the perianth. Styles 3; stigmas capitate. Achene 

 3-angled, rarely 3-winged. 



* Plants with scape-like peduncles, from a more or less woody and leafy 

 base; involucres umbellate or capitate, not virgately disposed. 



H Perianth narrowed to a slender stipe-like base. 



1. E. stellatnm, Benth. More or less tomentose, the stems diffuse 

 and leafy: leaves ovate-spatulate to oblanceolate : peduncles % 1 ft. 

 high, bearing an umbel of 2 4 usually elongated and cymosely divided 

 rays; the nodes all leaf y-bracted : fl. yellow: stipitate base of perianth 

 elongated. On Mt. Diablo and Mt. Hamilton. 



2. E. compositum, Dougl. More or less white- or yellowish-tomen- 

 tose, the leaves densely so beneath; these oblong-ovate, cordate at base, 

 acute or acutish, 13 in. long on rather long petioles: peduncles stout, 

 naked, % \% ft. high, nearly glabrous: umbel of 6 10 long rays, each 

 bearing a short several- rayed umbellule, subtended by whorls of linear- 

 oblanceolate leaflets: fl. 24 lines long, cream-colored or yellow, the 

 stipe-like base relatively short. Napa and Sonoma counties, at middle 

 elevations of the Coast Range. 



-t- -i Perianth abruptly contracted at base. 



3. E. 1 at i folium, Smith. Stout, tomentose throughout, the short cau- 

 dex sparingly branched and leafy : leaves oblong or oval, obtuse or acute, 

 1 2 in. long, rounded or cordate, or rarely cuneate at base, commonly 

 undulate, often glabrate above, 12 in. long, the stoutish petiole often 

 short and margined: peduncles stout, 620 in. high: bracts triangular: 

 involucres very-many-flowered, crowded in 1 3 large terminal heads, or 

 the peduncles more than once forked above and the heads smaller: 

 bractlets densely villous-plumose : fl. whi^e, the sepals broadly obovate. 

 In rocky or sandy places near the sea. 



4. E. ii iidum, Dougl. Much taller and more slender than the last, 

 the ovate or oblong leaves (% 2 in. long) densely tomentose beneath, 

 glabrate above: peduncle and loose panicle 1 2 ft. high, glabrous and 

 glaucescent, or somewhat floccose-tomentose : involucres 23 lines long, 

 nearly or quite glabrous, 3 6 in each cluster: fl. glabrous or villous, 1 

 \% lines long, white. Clayey banks and dry hills; a more inland species 

 than the last. July Oct. 



