334 COMPOSITE. Amhlyopaj^ims. 



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

 104. Villanova cknjsanthemoides, Gray, PI. Wright, ii. 96. — Along mountain water-courses, 

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



145. AMBLYOPAPPUS, Hook. & Am. ('A/x^Xvs, blunt, TraTTTr^, pap- 

 pus.) — Jour. Bot. iii. 321 ; Benth. & Hook. Gen. ii. 40G. Aromia, Nutt. Tran.s. 

 Am. PhiL Soc. vii. 395. Infantea, Remy, in Gay, Fl. Cliil. iv. 257, t. 48. — 

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

 in Bolivia), probably introduced into California. 



A. pusiilus, Hook. & Arn. 1. c. A span or two high, nearly glabrous, balsamic-viscid, 

 paniculately or corymbosely branched, with small short-peduncled heads t2rminating the 

 branches : leaves linear and alternate, entire or lower pinuately S-S-jiarted and opposite : 

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

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

 "(Chili.) 



146. SCHKtTHRIA, Roth. {Christian Schhuhr, 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-punctale. — Roth, Catalecta Bot. i. 110 ; Cass. ; Less., &c. Tetracarpum, 

 Moench, Meth. Suppl. 241. Schkuhria & Hopkirkia, DC. Prodr. v. 654, 660. 

 Schkuhria, Benth. & Hook. Gen. ii. 403, in part, excl. Achyropappus, &c. — Our 

 species, and aS'. 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 : stems diffusely corymbose-paniculate. 



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



])ercurrent costa projecting as a cusp : faces of tlie akeue conspicuously 3-nerved. — PI. 



Wright, ii. 94. Hopkirkia anthemidca, DC. Prodr. v. 660. — S.Arizona, Wrirjht, Lemmon. 



(Northern Mex., Hcenke.) 

 S. 'Wrightii, Gray, 1. c. Pappus shorter than the corolla; its palefe 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, Wriglit, Thurher, Lemmon. 



147. HYMEN6THRIX, Gray. (From ifxi^v, membrane, Opi^, 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 

 difl:'erent in the two species. 



H. "Wislizeni, Gray. Glabrous : lobes of the leaves often spatulate-linear and broadish : 

 heads radiate : involucre of com])aratively 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 below, naked and hispidulous above. — PI. Fendl. 



