Chrysogonum. ■ COMPOSIT.-E. 243 



B. tomentosa, Ndtt. 1. c. Canesceut throughout with soft and close pannose tomentutn, 

 uo hirsute or villous hairs, when glahrate hardly at all scabrous : stem a foot or two high, 

 rarely ouly a span high : leaves all obtuse, green above, geuerally whitish beneath ; radical 

 and lower cauline elongated-oblong and petioled ; upper cauliue usually ovate-oblong or oval, 

 sometimes subcordate-ovate, short-petioled or sessile heads fewer, in low specimens almost 

 solitary and longer-peduncled. — Torr. & Gray, Fl. ii. 282. B. pum/lu,'Natt. I.e. Silphium 

 puinilitm, IMichx. Fl. ii. 146. »?. tomcnfosum, pumilum, & rcticulatum? Pursh, Fl. ii. 578, 579. 

 S. Asteriscus, var. pumilum, Wood, Bot. 442. Poli/mnia CuroUniana, Poir. Diet. v. 505. — 

 Dry pine barrens, N. Carolina to Florida, Arkansas, and Missouri. 



Var. dealbata, Torr. & Gray, 1. c. More robust and leafy, 2 or 3 feet high, branch- 

 ing at sunnnit and bearing more numerous and siiorter-ped uncled heads: cauline leaves 

 broader and more sessile, densely white-tomeutose beneath ; lower broadly cordate, upper 

 often deltoid (with or without a subcordate base), either obtuse or acute. — Texas, Drum- 

 mtmd, Hall, Reirrchon, a very soft-canesceut form. Varies into a less canesccnt state, 

 approaching B. Texana, the leaves scabrous above (var. y, Torr. & Gray, 1. c), Arkansas, 

 Louisiana, and Texas. 



* * Stems commonly low and with long mouoccphalous peduncles; the earliest often produced 

 from near the root, and scapiform, the later from leafy stems or braiielies: leaves variable, all 

 attenuate at base, disposed to be pinuatitid or lyrate. 



B. subacaulis, Nutt. 1. c. Barely cinereous with minute often hi.spidulous pubescence (or 

 the peduncles sometimes hirsute), soon green, becoming a foot or so high and leafv : leaves 

 of oblong-linear or oblong-spatulate outline, irregularly sinuately or lyrately piunatifid, with 

 short obtuse lobes : akenes narrowly obovate-oval, merely carinately costate on the inner 

 face. — Torr. & Gray, Fl. ii. 282. Si/pJiium suhacaule, Nutt. in Am. Jour. Sci. v. 301 ; DC. 

 Prodr. V. 512. 5. iVuttallianum, Tow. Ann. Lye. N. Y. ii. 21G, as te syn. — Florida, in dry 

 pine barrens ; first coll. by Ware. 



B. lyrata, Bexth. Canesceut with minute white or gray tomentum : leaves at length 

 greenish above, variously lyrate-piuuatifld ; the lateral lobes obloug or narrower, obtusely 

 dentate, sometimes incised : akenes obovate, the costa of the inner face strongly carinate. 



— PI. Hartw. 17; Gray, PL Fendl. 78, & PI. Wright, i. 103. B. incisa, Torr. & Gray, Fl. 

 ii. 282. S!lj)hiam NutUdUanum, Torr. Ann. Lye. N. Y. ii. 216, excl. syu. — Plains and hills, 

 W. Texas and Arkansas to Arizona. (Mex.) 



Var, macrophylla. lladical leaves often a foot long, lanceolate-oblong or spatulate, 

 either merely crenate or piunatifid at base : later flowering stems sometimes 2 or 3 feet high. 



— S. Arizona, Lcmiuoa. 



72. CHRYSOGONUM, L. (Greek name of some plant in Dioscorides. 

 Linnaeu.s gives the derivation of his genus from xs^vao^, golden, and yow, knee ; 

 of no obvious application.) — Gasrtn. Fi'uct. ii. 43G, t. 174 ; Lam. 111. t. 713 ; DC 

 Prodr. V. 510; Torr. & Gray, Fl. ii. 274; Beuth. & Hook. Gen. ii. 350, excl. 

 syn. 3Iooma, &c. ; Gray, Proc. Am. Acad. xvii. 21G. Diotostephus, Cass. Diet, 

 xlviii. 543. — Single species: fl. spring and summer. 



C. Virginianum, L. Perennial from creeping rootstocks and sometimes by runners, 

 pubescent, often hirsute, flowering acaulesceutly from the ground, also with stems a span to 

 a foot liigli, bearing 3 or 4 pairs of long-petioled leaves ; these ovate, mostly obtuse and 

 crenate; cauline rarely subcordate and equalling or shorter than their petioles, or the radical 

 obovate with cuneate attenuate l)ase : peduncles solitary in the forks and terminal, all but the ' 

 radical ones elongated : involucre one-third and yellow rays half inch long. — Spec. ii. 920 

 (Pluk. Aim. t. 83, f. 4, & 242, f. 3) ; Walt. Car. 217; Michx. Fl. ii. 148; Torr. & Gray, 1. c. 

 C. Virgmianum & C. iJiotostepIuis, DC. I.e. Diolostephus repens, Cass. I.e. — Dry ground, 

 S. Penn.sylvaiiia to Florida. Varies considerably according to age and season, usually low 

 when blossduiing l)cgins. 



Var. dentatum, (tuay. Leaves deltoid-ovate, acute, coarsely dentate-serrate, the tip 

 and teeth, also the tips of the bracts of the outer involucre, terminated by a more conspicu- 

 ou.<-, callous mucro. — Bot. Gazette, viii. 31. — High Island at the falls of the Potomac above 

 Washington, J. Donnell Smith, Ward, Vasey. 



