450 COMPOSITE, 



* * Taller, leafy nearly to the summit; no floccose wool; heads solitary or 



subracemose. 



4. H. heterochroma, Gray, Proc. Am. Acad. vii. 359 (1867). Stout, 

 2 ft. high or more, annual: leaves oblong, saliently dentate: involucre 

 )?4 in. high, of linear-lanceolate attenuate-acute bracts: rays many, 3 — 4 

 lines long, rose-purple, but occasionally reduced or obsolete: palese of 

 the pappus oblong, the two over the angles of the achene longer than 

 the others, the shorter ones truncate-lacerate. — Yosemite Valley and 

 southward. 



5. H. brevifolia, Gray, 1. c. Slender, 1 ft. high; character of root 

 unknown : stem or simple branches clothed with rather small spatulate- 

 obloDg denticulate leaves, the largest only 1}4 in- long: involucre % ^^■ 

 high, of loose linear bracts: rays 10 — 12, only 3 4 lines long: palea? of 

 the pappus nearly entire. — Foothills along the Merced Eiver, and near 

 the Yosemite. 



83. RIGIOPAPPUS, Grra?/. Heads with short narrow ligulate rays; 

 all the flowers yellow. Involucre turbinate-campanulate, its bracts 

 nearly linear, equal, rather rigid, involute in age. Disk-corolla small, 

 with short tube, long narrow throat, and 3 — 5 short erect teeth. Style 

 branches with slender-subulate hispidulous appendage and short linear 

 stigmatic part. Pappus alike in disk and ray, of 3—5 opaque paleaceous 

 awns; the linear pubescent achene transversely rugose. 



1. R. leptocladns, Gray, Proc. Am. Acad. vi. 548 (1865). Slender 

 erect annual, 6—12 in. high, simple below, above with few slender 

 corymbose branches: leaves alternate, narrowly linear, sessile, erect, 

 entire, hirsutulous or glabrate, those of the filiform branchlets subulate: 

 palefe of pappus % — /S ^^ long as the long slender rugulose achene. — 

 Open glades among sparsely wooded hills. May. 



84. AMBLYOPAPPUS, Hooker cfc Aniot. Rigidly erect panicled 

 small seaside annual, with narrow leaves, gummy and sweet-scented 

 herbage, and numerous small rayless heads. Bracts of involucre 5 or 6, 

 broadly obovate, their middle part in age somewhat carinate-coucave. 

 Receptacle small, conical. Corollas all short-tubular; those of the 

 pistillate flowers minutely 2 — 3-toothed, of the perfect, 5-toothed, the 

 teeth soon connivent. Achenes obpyramidal, pubescent. Pappus of 

 8—12 oblong obtuse palese about equaling the corollas. 



1. A. pnsilliis, H. &. A. in Hook. Jouru. Bot. lii. 321 (1841) Aromia 

 tenuifolia, Nutt. Trans. Am. Phil. Soc. vii. 396 (1841). Plant %~1 foot 



