4 S6 



COMPOSITAE. 



Vol. lit. 



24. Helianthus laetiflorus I'crs. Showy Sun- 

 flower. Fig. 4484. 

 Helianthus laetiflorus Pits. Syn. 2: 476. 1807. 



Perennial; stem scabrous or hispid, leafy, 4-8 high. 

 Leaves oval-lanceolate or ovate-lanceolate, shprt-peti- 

 oled, 3-nerved, rough on hoth sides, narrrowed at the 

 base, acute or acuminate at the apex, serrate or serru- 

 late, 4'-io' long, i'-li' wide, the upper often alter- 

 nate ; heads usually several, 2'-4' broad, mostly short- 

 pedunclcd ; bracts of the hemispheric involucre ovate- 

 lanceolate, or oblong-lanceolate, imbricated in only 2 or 

 3 series, ciliate, otherwise nearly glabrous, appressed or 

 but little spreading, shorter than or equalling the yellow 

 disk; rays 15-25, showy; chaff of the receptacle entire, 

 or sometimes 3-toothed. 



On prairies and barrens, Pennsylvania to Minnesota. Re- 

 corded as adventive in Massachusetts. Aug.-Sept. 



25. Helianthus tomentosus Michx. Woolly 



Sunflower. Fig. 4485. 



H. tomentosus Michx. Fl. Bor. Am. 2: 141, 1803. 



Perennial ; stem stout, hirsute or hispid, especially 

 above, branched. 4-io high. Leaves rather thin, 

 ovate, or the lower oblong, mostly alternate, 3-ribbed 

 above the base, gradually or abruptly contracted into 

 margined petioles, rough above, softly villous-pubes- 

 cent beneath, sparingly serrate, the lower often 1 

 long and 4' wide ; heads commonly several or nu- 

 merous, 3'-4' broad ; involucre hemispheric, its bracts 

 imbricated in many series, linear-lanceolate, long- 

 acuminate, squarrose, densely hirsute and ciliate, 

 usually longer than the broad yellowish disk; chaff 

 of the receptacle and lobes of the disk corolla pubes- 

 cent ; pappus of 2 subulate awns. 



In dry soil, Virginia to Georgia and Alabama. Re- 

 ported from Illinois, probably erroneously. Aug.-Oct. 



26. Helianthus tuberosus L. 

 choke. Earth Apple. 



Terusalem Arti- 

 Fig. 4486. 



Helianthus tuberosus L. Sp. PI. 905. 1753. 

 Helianthus tuberosus subeanescens A. Gray, Syn. Fl. 1 : 

 Part 2, 2S0. 1884. 



Perennial by fleshy thickened rootstocks, bearing 

 tubers; stems hirsute or pubescent, branched above, 

 6-i2 high. Leaves ovate or ovate-oblong, rarely 

 ovate-lanceolate, firm, 3-nerved near the base, nar- 

 rowed, or the lower rounded, truncate or subcordate 

 at the base, acuminate at the apex, rather long- 

 petioled, scabrous above, finely pubescent or canes- 

 cent beneath, serrate, 4'S' long, 1*' 3' wide, the up- 

 per alternate, the lower opposite ; heads several or 

 numerous, 2'-3i' broad ; involucre hemispheric, its 

 bracts lanceolate, acuminate, hirsute or ciliate, squar- 

 rose; disk yellow; rays 12-20; chaff of the receptacle 

 acute and pubescent at the summit ; achenes pubescent. 



In moist soil. Nova Scotia and Ontario to Manitoba. 

 Georgia and Arkansas and Kansas. Often occurs along 

 roadsides in the east, a relic of cultivation by the abo- 

 rigines. Now extensively grown for its edible tubers. 

 Canada potato. Girasole. Topinambour. Sept.-Oct. 



67. RIDAN Adans. Fam. PI. 2 : 130. 1763. 

 [Actinomeris Nutt. Gen. 2: 181. 1818.] 

 Rough-pubescent, rather coarse, herbs with alternate or opposite, simple, more or less 

 toothed leaves, usually decurrent on the stem and branches, and corymbose, radiate or discoid 



