120 COMPOSITJS. PentachcBta. 



§ 1, Flowers of both ray and disk golden yellow: involucre of comparatively 

 numerous and regularly imbricated bracts. 



P. aurea, Nutt. 1. c. At length diffusely branched, 3 to 12 inches high: heads mostly 

 large for the size of the plant and inany-Howered, but greatly varying : rays 7 to 40 (2 to 5 

 lines long) : bracts of the involucre broadly lanceolate, mostly setaceous-acuminate, with 

 green centre and broad scarious margins : aicenes villous-pubesceut : pajipus-bristles 5, some- 

 times 6 to 8, as long as disk-corollas. — Gray, Bot. Mex. Bound. 81, Bot. Calif. 1. c. — Open 

 and dry ground, in the southernmost counties of California; first coll. by Nuttall. 



§ 2. Flowers of the ray white or purple-tinged, sometimes wanting or else few 

 and wanting the ligule: disk-corollas yellow or yellowish, or changing to purple 

 in age : bracts of involucre somewhat equal and fewer, mostly obtuse and nar- 

 rowly scarious-margined. 



P. exilis, Gray, 1. c. A span or so high, with simple or from the base simply branched 

 mouoccphalous erect stems: heads in the larger form (here taken as the type) many- 

 flowered, with hemispherical or broadly campanulate involucre (3 lines high), and 8 to 14 

 oblong rays, tliese 2 lines long : akeues oblong-turbinate, villous : pappus-bristles 5, shorter 

 than disk-corollas, in some plants abortive or obsolete. — Bot. Calif. 1. c. ; Greene in Bot. 

 Gazette, viii. 256. — Dry hills, middle part of California, from Santa Clara Co. northward. 



Var. aphantochaeta, Gray, 1. c. More or less depauperate, 2 to 4 inches high : 

 heads narrower, from rather few- to 25-flowered, discoid, mostly having 3 to 5 female flowers 

 with corolla destitute of ligule, sometimes these wanting : pappus reduced to 3 or .'3 short 

 cusps or obsolete. — P. aphantoclueta, Greene in Bot. Gazette, 1. c. Aphantochatn exilis, 

 Gray, Pacif. R. Rep. iv. 99, t. 11, a delicate and few-flowered form. — Dry ground, from the 

 Salinas Valley to El Dorado Co., first coll. by Biijclow. Var. discoidea. Gray, 1. c, is partly a 

 small form of this without female flowers, and partly the following, into which it may pass. 



P. alsinoides, Greene, a span high, at length diffusely and several times branched from 

 the base, with pedunculated discoid heads in the forks : involucre only 2 lines long, of only 

 5 to 7 bracts, " 3-5-" or 6-7-flowered : flowers apparently all hermaphrodite : pappus-bristles 

 3 or 4, fully equalling the corolla and as long as the obovate-clavate pubescent akenes, rarely 

 obsolete in some flowers. — Bull. Torrey Club, ix. 109, & Bot. Gazette, 1. c. — Hills or dry 

 ground around San Francisco Bay to El Dorado Co., fii-st coll. by Kellogg and Bolander. 



P. GRACILIS, Benth. in Hook. Ic. t. 1101, from Mexico, is Oxi/pappus, Benth. 



25. BRADBtTRIA, Torr. & Gray. (In memory of John Bradbury, who 

 collected plants on the Missouri which were published in Pursh's Flora.) — Fl. 

 ii. 250; Benth. & Hook. Gen. ii. 251. — Single species. 



B. hirtella, Torr. & Gray, 1. c. Annual, branched from the base, a foot or so high, hispid : 

 slender branches terminated by single rather small heads of yellow flowers : radical and 

 lower cauline leaves narrowly spatulate ; those of the flowering branches small, spatulate- 

 liuear to nearly filiform, mucronate-pointed : rays 3 or 4 lines long. — Dry ground, Texas, 

 Drumiiiond, Wright, Lindheimcr, &c. 



26. HETER0TH£;CA, Cass. ("Erepo?, different, Oi'jK-q, case, from the 

 unlike akenes of ray and disk.) — N. American and Mexican herbs (probably 

 only three species, two of them very variable), with the aspect of Chrysopsis, 

 hirsute or scabrous : flowers yellow : pappus reddish or ferruginous : lower leaves 

 at base of petiole commonly with a foliaceous stipuliform dilatation, upper partly 

 clasping. Peduncles and involucre more or less glandular. A bristle or two of 

 pappus rarely found on ray-akenes. — -Bull? Philom. 1817, & Diet. xxi. 130 ; 

 DC. Prodr. v. 316 ; Torr. & Gray, Fl. ii. 251. 



H. Lamarckii, Cass. 1. c. Biennial or sometimes annual, 1 to 3 feet high, somewhat 

 heavy-scented, branching, usually bearing numerous corymbiform-paniculate rather small 

 heads : radical leaves oval or oblong, sleuder-petioled ; cauline oblong, the upper mostly 



