DiduEtophora. COMPOSITE. 165 



K. effusa, Grat. Perennial, often 2 feet high, with simple stem branching above into an 

 effnse ample panicle; leaves (an inch m- less long) hispid as well as the stem, rigid and sca- 

 brous, oblong, mostly with a broad sessile base : heads very numerous : involucre more 

 turbinate: r;i_vs 4 to 7, white: disk-flowers somewhat more numerous, apparently always 

 sterile, and with elongated linear-lanceolate style-appendages : fertile akenes oljovate, flat, 

 callous-nerved at the margins (or with one margin 2-uerved). — PI. Lindh. ii. 221; PI. 

 Wright, i. 93. — Hillsides, central parts of Texa.s, Bulnndier, Lindheiiner. 



39. CH^ETOPAPPA, DC. (XmV,,. bri.stle, and Wtt-oc, pappus.) — Low 

 and sm;ill Texano-Mt-xican winter annuals, diilusely liranclied; the branches 

 terminated Ijy small heads : rays white or i)arple : leaves entire, the lower spatu- 

 late, upper irradually becoming linear or reduced to subulate bracts. Fl. sprinj.' 

 and early summer. — Cliatantliera, Xutt. Jour. Acad. PliDad. vii. 111. ChcB- 

 tophora, Xutt. in DC. ClKetopappa & Distasis, DC. Prodr. v. 301, 271) ; Benth. 

 & Hook. (ren. ii. 2GS. Diplostfhna, Gray, PI. Fendl. 72. 



•C. asteroides, DC. 1. c. Slender, 2 to 10 inches high, pubescent: involucre (2 lines long) 

 ratlier narrow, of 12 to 14 bracts: rays 5 to 12 : disk-flowers 8 to 12 : style-appendages very 

 obtuse : akenes slender, little compressed, uljscurely few-nerved, pubescent, all the central 

 ones sterile and often awuless : paleiE of the pappus very thin and hyaline, narrowly oblong, 

 not rarely lacerate or cleft. — Torr. & Gray, PI. ii. 187. Chmtanthera asteroides, K'utt. 1. c. — 

 Dry ground, Texas to Arkansas and the borders of Missouri. (.Vdjacent 5Iex.) 



Var. imberbis, Gray. Awns of the pappus wanting in all the flowers: the palese 

 rather broader and sometimes coroniform-concreted. — Proc. Am. ^i.cad. xvi. 82. — E. Texas, 

 Wright. 



C. Parryi, Ge.\t. ilure rigid, 9 inches or more high : leaves subcoriaceous, hispidulous 

 andglabrate: involucre (3 lines long) turbinate: rays 6 or 7 : style-appendages short and 

 very obtuse; akenes quite glabrous; the fertile ones fusiform and somewhat compressed, 

 4-uerved, with a pappus of 4 or 5 firmer and cuneiform-cjuadrate palea' which are laciniately 

 fimbriate afthe truncate apex, and of few or sometimes .solitary more delicate awns, these 

 occasionally little longer than the paleae, sometimes wanting; disk-akenes mostly inane and 

 awuless. — Proc. Am. Acad. x\i. 82. Diitasis modesta, var.. Gray, Bot. Mex. Bound. 78. — 

 Mt. Carmel, on the Rio Grande, between Texas and Jlexico, Pnrry. 



C. modssta Gray, 1. c. Less slender and pubescence more hirsute than in C. asteroides : 

 involucre broadly campanulate ; its bracts obtuser and more numerous : rays 9 to 20 : dLsk- 

 flowers 40 to 60, all but the central fertile ; their style-appendages narrower and acutisli : 

 akenes oblong or linear, much compressed, pubescent Mhen young, with merely marginal 

 nerves or occasionaUv a facial one, only the central ones sterile : pappus of 5 oblong erose- 

 tmncjite at length subcoriaceous paleai, alternating with as many rather rigid awns. — Dis- 

 tasis modesto, DC. Prodr. v. 279. Dipl"stehi,n btlliotdes, Gray, PI. Peudl. 73 — Dry ground, 

 Texas, Berlandier, Wright, &c. ( Adjacent ilex. ) 

 DfsTAsis? HETEROPHVLLA, Hemsl. Biol. Centr.-Aju. Bot. ii. 119, of Mexico, is hardly of 



this genus, probably not of the tribe. 



40. M0N6PTIL0N, Torr. & Gray. (Mdi/os, single, tttlXov, feather, al- 

 luding to the solitary plumose bristle of the pappus.) — Jour. Bost. Xat. Hist. Soc. 

 V. 106, t. 13; Benth. & Hook. Gen. ii. 307; Gray, Bot. Calif, i. 306. — Single 

 species. 



M. bellidiforme, Tokk. & Gray, 1. c. A small but pretty annual, much branched from 

 the verv base, depressed, villous-hirsute : heads terminating the numerous leafy branchlets, 

 haU-iuch in diameter, inclusive of the white or violet-purple rays : leaves small, spatulate or 

 linear-spatulate, the uppermost involiicrate around the head. —Arid or desert plains, S. E. 

 California to S. "O'. Utah, Fremont, Parry, Palmer, Parish. 



41. DICH-^TOPHORA, Gray. (\i'?, x«''"?> "^of^- bearing two bristles, 

 i. e. pappus-awns.) — PI. Fendl. 73. — Single species ; in Benth. & Hook. Gen. 



