334 COMPOSITE. AmUyopappm. 



by the base of the corolla. Proc. Am. Acad. xix. 28. Amauria ? dissecta, Gray, PI. Fendl. 

 104. Villanova chrysanthemoid.es, Gray, PI. Wright, ii. 96. Along mountain water-courses, 

 Colorado to S. Arizona; first coll. by Fremont. 



145. AMBLYOPAPPUS, Hook. & Am. ('A/i/3Xw, blunt, ira*?, pap- 

 pus.) -Jour. Bot. iii. 321 ; Benth. & Hook. Gen. ii. 406. Aromia, Nutt. Trans. 

 Am. Phil. Soc. vii. 395. Infantea, Remy, in Gay, Fl. Chil. iv. 257, t. 48. 

 Low annual (of Chili, and Schkuhria pusilla, Wedd., is perhaps a second species 

 in Bolivia), probably introduced into California. 



A. pusillus, HOOK. & ARN. 1. c. A span or two high, nearly glabrous, balsamic-viscid, 

 pauiculately or corymbosely branched, with small short-peduncled heads tarminatiug the 

 branches : leaves linear and alternate, entire or lower piunately 3-5-parted and opposite : 

 involucre 2 lines high, equalling the yellowish flowers. Aromia tenuifolia, Xutt. 1. c. In- 

 fantea Chilensis, Rcmy, in Gay, 1. c. Around San Diego, California, and southward. 

 (Chili.) 



146. SCHKtJHRIA, Roth. (Christian Schkuhr, of Wittenberg.) - 

 Slender and paniculately much branched annuals (Mexican and Andean), some- 

 what pubescent, never tomentose ; the small pedunculate heads of yellow (rarely 

 purplish) flowers terminating the branchlets : leaves alternate, or the lower 

 opposite, pinnately 3-7-parted or uppermost entire, the divisions and rhachis 

 filiform. Herbage sometimes minutely resinous-atomiferous and the leaves im- 

 pressed-punctate. Roth, Catalecta Bot. i. 116 ; Cass. ; Less., &c. Tetracarpum, 

 Moeuch, Meth. Suppl. 241. Schkuhria & ffopkirkia, DC. Prodr. v. 654, 660. 

 Schkuhria, Benth. & Hook. Gen. ii. 403, in part, excl. Achi/ropappus, &c. Our 

 species, and S. Wislizeni of Northern Mexico, form a section (the genus Hop- 

 kirkia, DC.), with leaves more commonly only 3-parted and on the branches 

 entire, heads only 3-5-flowered, with a single ray-flower or none: obpyramidal 

 akenes in length only about double the width of the summit, their angles very 

 densely long-villous, some hairs also on the faces : scarious tips of involucral 

 bracts purple-tinged : sterns diffusely corymbose-paniculate. 



S. Hopkirkia, GRAY. Pappus equalling the corolla; its paleae all alike, ovate-oblong, with 

 percurreut costa projecting as a cusp: faces of the akene conspicuously 3-nerved. PI. 

 Wright, ii. 94. Hopkirkia anthemidea, DC. Prodr. v. 660. S. Arizona, Wright, Lemmon. 

 (Northern Mex., Hanke.) 



S. "Wrightii, GRAY, 1. c. Pappus shorter than the corolla; its paleae all obovate and obtuse 

 or erose-truncate, destitute of costa, merely thickened at very base : akenes rather less thick 

 and faces less striate. S. Arizona, Wright, T/iurber, Lemmon. 



147. HYMEN6THRIX, Gray. (From fyufo membrane, Optt, bristle, 

 the pappus a combination of awn and thin palea.) - - Herbs of Arizona and 

 vicinity, glabrous or somewhat pubescent ; with probably annual or perhaps per- 

 ennial root, branching stems of 1 to 3 feet high, alternate leaves once to thrice 

 parted into linear divisions or lobes, and numerous corymbosely cymose heads 

 (about one-third inch high) ; the corollas yellow or white and purple, strikingly 

 different in the two species. 



H. "W^islizeni, GRAY. Glabrous : lobes of the leaves often spatulate-linear and broadish : 

 heads radiate : involucre of comparatively narrow acutish and yellow-tinged bracts, hardly 

 any accessory ones : corollas yellow ; those of the disk with oblong lobes only half the length 

 of the narrowly obconical throat: style-tips pointless: akenes rather slender, barely pubes- 

 cent: pappus-awns narrowly margined helow, naked and hispidulous above. PI. ITendl. 





