BLAKE. — E^X'ELIA AND RELATED GENERA. 355 



linear-oblong, 2 cm. long, 3-4.5 mm. wide; disk-corollas 7 mm. long 

 (tube 3 mm.), hairy on teeth and base of tube; pales 13.5 mm. long, 

 laterally 1-toothed, glandular-hairy on keel and tip; achene oblong, 

 10 mm. long, 3.5 mm. wide, silky-^^illous on body and margin, awnless 

 or with two subulate awns 1.8 mm. long, the squamellae almost com- 

 pletely united. 



Tithonia argophi/lla D. C. Eaton in Wats. Bot. King's Rep. v. 423 

 (1871). 



Encelia (Geraea) argophjUa Gray, Proc. Am. x\cad. viii. 657 (1873); 

 Jones, 1. c. 702 (1895). 



Helianthella argophylla Gray, Proc. Am. Acad. xix. 9 (1883); Co- 

 ville, 1. c. (1893), as to name only. 



Enceliopsis argophylla A. Nels. 1. c. (1909). 



Specimens examined: Utah: St. George, 1870, Palmer (fragments 

 of TYPE in Gray Herb.); Nevada: salty cliffs, salt mine near Stone's 

 Ferr\', near the Colorado River, alt. 366 m., 11 April 1894, Jones 

 5032q (hb. Jones). 



GERAEA Torr. & Gray (yepmos old, from the canescent-villous 

 achenes). Heads medium-sized or rather large, many-flowered, 

 radiate or discoid, the rays neutral; flowers all yellow. Involucre 

 hemispheric, the scales 2-3-seriate, linear or broadly oblong, equaling 

 or shorter than the disk. Receptacle flattish; pales softly scarious, 

 conduplicate, falling with the achenes. Rays when present cuneate, 

 the tube hairy; disk-corollas with c.ylindric tube and broader throat, 

 limb hairy and 5-toothed. Style liranches long, hairy. Disk-achenes 

 strongly compressed, villous especially on the edges, narrowly cuneate 

 with narrow whitish margin produced into two strong awns decurrent 

 into the conspicuous crown. — Annuals or biennials (base unknown 

 in G. viscida), glandular-pubescent, simple or branched, with alternate 

 dentate leaves and usually few paniculate heads. Type species G. 

 canescens Torr. & Gray {Encelia eriocephala Gray). — Two species of 

 southwestern United States and adjacent Mexico. — The squamella- 

 ceous corona of the ovary, from which the thick crown of the fruit is 

 at least in part developed, is distinct enough in G. viscida, although 

 visible in G. canescens only as a narrow border cormecting the decurrent 

 based awns. It seems quite analogous with the corona of completely 

 fused squamellae in such a species of Enceliopsis as E. nutans. 



Geraea Torr. & Gray, Am. Journ. Sci. ser. 2. iii. 275 (Mar. 1847); 

 Proc. Am. Acad. i. 48^1848). 



