Aplopappus. COMPOS ITiE. 125 



t. 10. Centanridium Drummondii , Torr. & Gray, FI. ii. 246; Gray, PI. Liiulli. ii. 223. 

 Mucliceranthera grandlflont, Buckley in I'roc. Acad. I'hilad. 1861, 456. — Open woods, Texas 

 Betiandier, Druniiiiond, Li lul/w inter, &c. ; H. all summer. 



30, APLiOPAPPUS, Cass. •('A-Ao'os, 7ru7r7ro9j simple pappus.) — A large 

 American genus (chiefly W. North American and Chilian) the analogue of Aster 

 in the heterochromous division and equally polymorphous ; mostly herbaceous 

 perennials, some suffruticose or even shrubby, a few annual : the fiovvers all 

 yellow, produced in summer and autumn. — Diet. Ivi. 1 68. Ilaplopappus & Eri- 

 cameria, Benth. & Hook. Gen. ii. 25;>, 2.55. — Note that one or two species 

 occasionally and certain species uniformly want the ray-flowers, obliterating the 

 distinction between this genus and the following ! 



§ 1. Prionopsis, Gray. Heads very large and broad: involucre depressed- 

 hemispherical, of lanceolate acuminate bracts, the outer mostly foliaceous and 

 s[)reading : rays very numerous : disk-corollas narrow, merely 5-toothed : style- 

 appendages short and rather obtuse: akenes very glabrous; those of the ray 

 short, turgid-elliptical ; of the disk oblong or narrower, and the central ones 

 inane : pappus of very rigid and unequal bristles and comparatively little nu- 

 merous ; the innermost and larger ones somewhat flattened toward the l)ase and 

 their margins scabrous-ciliolate ; the outermost very small and short : root annual 

 or biennial. — PI. Wright, i. 98. Prionopsis, Nutt. Trans. Am. Phil. Soc. 

 n. ser. vii. 329. — (Connects with Xanthisma and has the foliage of Griudelia.) 



A. ciliatus, BC. Very glabrous : stem 2 to .5 feet high, hearing few or several somewhat 

 cymosc-clustered heads (with the disk an inch in diameter), equably leafy to the top: leaves 

 oval or the lower obovate (1 to 3 inches long), very obtuse, veiny, evenly and somewhat 

 pectinately dentate with bri.stle-pointed teeth : pappus of the fertile akenes disposed to be 

 deciduous in a ring. — Prodr. v. 340; Gray, PI. Wright, i. 98. Donia ci/iata, Nutt. .Jour. 

 Acad. Pliilad. ii. 118; Hook. Exot. Fl. i. t. 45. Prionopsis ciliata, Nutt. 1. c. ; Torr. & 

 Gray, Fl. ii. 245. — Hillsides and river-banks, Missouri and Kansas to Texas. 



§ 2. Aplopappus proper. Heads large or middle-sized, or sometimes small, 

 commonly broad and with involucre of firm well-imbricated or rigid bracts : rays 

 numerous, several, or rarely wanting : disk-corollas narrow, merely 5-toothed : 

 style-appendages from ovate to linear-subulate : pajipus commonly fuscous or 

 rufous, and more or less rigid. (Habit and special characters various, but the 

 groups too confluent and indefinite for first-class sections.) 



* Heads rayless : bracts of the involucre riij-id, appressed-imbricate with the outer successively 

 shorter, all with abrupt and more or less spn^ading herbaceous tips: style-appendages ovate- or 

 oblong-lanceolate: pappus rather rigid: leaves coriaceous, mostly oblong and spiuulose-dentate. 

 — Aplopappus § Aplodiscus, Torr. & Gray, I'"l. ii. 242, excl. the tirst species, which is § Aplodis- 

 cus, DC. § Ilaplodiscus & Eiiocarpan, Dcnth. & Hook. 1. c. — (One of the transitions to Bujt- 

 lovia § Aplodiscus.) 



A. squarrosus, Hook. & Arn. Suffruticose, 2 or 3 feet high, somewhat pubescent, gland- 

 ular and glutinous : leaves thickly dentate (about incli long) : heads numerous and spicately 

 thyrsoid at the end of the branches, half-inch long : involucre elongated-turbinate ; its bracts 

 imbricated in many ranks, the lower usually imbricated on tlie peduncle, their tips mostly 

 squarrose and glandular: akenes fusiform, glabrous, or sparsely pubescent. — Pot. Beech. 

 146; Torr. & Gray, Fl. ii. 242. Pi/nvcoma fpindclioides, DC. Prodr. v. 350. IIomopap/>us 

 sfjiiarrosus, Nutt. Trans. Am. Phil. Soc. 1. c. 332. — Dry hills on the coast of Californiii, from 

 Monterey to San Diego; first coll. by Dowjlas. Also on the foot-hills of the San Bernardino 

 Mountains, Parish, &c. 



A. Nuttallii, Torr. & Gray, 1. c. Herbaceous from a ligneous stock, a span to a foot 

 high: leaves from spatulate oblong to almost lanceolate, rather sparsely pectinately dentate: 



