358 COMPOSITE. Mymenatherum. 



pappus of 18 or 20 very narrow palese, of 2 or 3 lengths; the smaller attenuate into a short 

 single awn, the larger into a much longer capillary awn, with a delicate short one at each 

 side of its base, or rarely an additional pair of seta. — PL "Wright, i. 116. — Prairies, S. W. 

 Texas and New Mexico, Wright. (Chihuahua, adj. Mex., Thurber.) 



H. Wrightii, Gray. Erect or diffuse, a foot or less high from a firm annual or perhaps 

 perennial root : branches rather simple, bearing few or solitary heads on peduncles 1 to 3 

 inches long : leaves not rigid, narrowly linear or almost filiform (an inch or more long),setu- 

 lose-mucronate, many entire, some with 1 to 3 small subulate lobes : involucre fully 3 lines 

 high, 16-20-toothed : palese of the pappus 10, all slenderly 3-awned from a short lanceolate 

 base; lateral awns with subulate base, half the length of middle one. — PI. Fendl. 89, PI. 

 Lindh. ii. 229, & PI. Wright. 1. c. — Prairies of Texas, Wright, Lindheimer, &c. 



H. tenuilobum, DC. Diffusely branched and spreading from a seemingly annual but 

 sometimes more enduring root: branches a span to a foot long: heads on filiform (1 to 4 

 inches long) peduncles : leaves rather rigid, all pinnately parted into 7 to 11 subulate-filiform 

 setulose-mucronate divisions (of only 2 to 4 lines in length) : involucre 3 lines high, about 

 12-toothed : palese of the pappus 10, more rigid, all nearly similar and bearing two lateral 

 and a middle longer stouter awn, the latter hardly longer than the lanceolate paleaceous por- 

 tion (which, however, sometimes splits away from the awn on each side), rarely one or two 

 smaller lateral Betas or cusps. — Prodr. v. 642. H. tenui/olium, Gray, PI. Wright. 1. c, not 

 Cass. — S. Texas along and near the Rio Grande, Berlandier, Wright, &c. (Adj. Mex.) 



-1— +- All 10 pales of the pappus nearly similar and tapering into a single short awn, and the 

 larger mostly 2-setulose: leaves acerose. 



H. Tlrlirberi, Gray. Habit and character of a more leafy-stemmed form of H. pentachcetum : 

 palese of the pappus not distinctly in two series, all narrowly lanceolate, alternate shorter 

 ones subulate-awn-pointed, the others with awn rather shorter than the palese, and a pair of 

 obscure or more manifest setulose teeth at its base. — Proc. Am. Acad. xix. 41. B. tenui- 

 folium, var. ? Gray, PI. Wright, ii. 93. — Texas or adjacent New Mexico, on the Mexican 

 border near El Paso, Wright. Corralitas, Thurber. (Apparently also Northern Mexico, 

 Parry.) 



-i— H— -t— Pappus manifestly double and dimorphous, of 10 scarious palese; the 5 outer shorter ,- 

 spatulate or oblong, obtuse and pointless; inner lanceolate or oblong, bearing a single awn, of 

 equal or greater length, between a pair of cusps or subulate or sometimes aristellate teeth. 



-w- Low and diffuse suffruticulose perennials, minutely cinereous-pubescent or glabrate, not woolly, 

 much branched from the base: leaves rigid or rigidulous, pinnately parted into few or several 

 mostly filiform or acerose entire divisions, subulate or setulose-mucronate at tip : heads on elon- 

 gated filiform peduncles. 



H. Hartwegi, Gray. A span, or two high, nearly herbaceous and glabrous : leaves chiefly 

 opposite, of few rather long filiform-aeerose divisions : heads numerous : involucre 'rather 

 narrow, 2 lines high, almost naked at base : outer paleas of pappus subcoriaceous, with trun- 

 cate summit obscurely denticulate. — PI. Wright, i. 117. H. Berlandieri, Benth. PI. Hartw. 

 18, not DC. — W. Texas to S. Arizona, Wright, Lemmon. (Mex.) 



H. pentachEetum, DC. Decidedly suffruticulose, low, diffuse, cinereous-puberulent, 

 sometimes glabrate and rather shining, sometimes the foliage canescent with short and fine 

 spreading pubescence : leaves rigid, upper alternate, divisions slender subulate-acerose : in- 

 volucre from broadly campanulate to hemispherical, 2 or 3 lines high : outer palese of the 

 pappus thinnish, usually erose at summit. — Gray, PI. Wright, i. 117. H. pentachcetum 

 (the outer pappus overlooked) & H. Berlandieri, DC. Prodr. v. 642. — Dry hills, Texas (first 

 coll. by Berlandier) to Arizona and S. Utah : very variable. (Mex.) 



H. Trectilii, Gray. Diffuse, nearly herbaceous, almost glabrous, with loose elongated leafy 

 branches and very scattered heads : leaves perhaps rather succulent, pectinately parted into 

 linear-subulate equal short (2 or 3 lines long) divisions, which are rather narrower than the 

 rhachis : involucre (3 lines high) and pappus of the preceding. — Proc. Am. Acad. xix. 42. 

 — S. E. Texas, Tre~cul, in herb. Mus. Paris. 



++ ++ Low and densely floccose-lanate and soft-leaved annual. — Gnaphaliopsis, DC. 

 H. Gnaphaliopsis, Gray. Depressed or diffusely spreading, clothed even to the involucre 

 with dense white wool in the manner of a Cudweed, leafy up to the sessile or short-peduncled 

 solitary heads : leaves mostly alternate, spatulate, entire, barely half-inch long : involucre 



