458 CAEDUACEAE. 



34. ERECHTITES Eaf. Fl. Ludov. 65. 1817. 



Erect, usually branching herbs, with alternate leaves, and (in our species) 

 rather large, discoid, many-flowered heads of whitish flowers, corymbose-panicu- 

 late at the ends of the stem and branches. Involucre cylindric, swollen at the 

 base, its principal bracts in 1 series, linear, with or without much smaller 

 outer ones. Eeceptacle concave, naked. Marginal flowers in 2-several series, 

 pistillate, fertile, their corollas filiform, the limb 2-4-toothed. Central flowers 

 perfect, fertile; corolla narrowly tubular, the limb 4 5-toothed, the style- 

 branches elongated, truncate or obtuse at the summit. Anthers obtuse and 

 entire at the base. Achenes linear-oblong, angled or striate. Pappus of 

 copious capillary soft smooth white bristles. [Ancient name of some ground- 

 sel.] About 12 species, natives of America and Australasia. Type species: 

 Erechtites praealta E&f. 



1, Erechtites hieracifolia (L.) Eaf.; DC. Prodr. 6: 294. 1837. 

 Senecio Tiler acifolius L. Sp. PI. 866. 1753. 



Annual, glabrous, or somewhat hirsute; stem striate, succulent, usually 

 branched, 3-25 dm. high. Leaves thin, lanceolate or ovate-lanceolate, dentate 

 and often deeply incised, 5-20 cm. long, the upper sessile or auriculate- clasp- 

 ing, mostly acuminate, the lower usually narrowed into petioles; heads 12-20 

 mm. long, about 6 mm. in diameter, the involucre conspicuously swollen at the 

 base before flowering,, its bracts numerous, striate, green, with narrow scarious 

 margins; pappus bright white. 



Cultivated fields and coppices, Andros : West Indies and temperate and trop- 

 ical continental America. FIRE-WEED. 



35. CIRSITIM [Tourn.] Mill. Gard. Diet. abr. ed. 4. 1754. 



Erect, branched or simple, prickly herbs, some species acaulescent, with 

 alternate or basal, sinuate-dentate lobed or pinnatifid, usually very spiny 

 leaves, sometimes decurrent, and large many-flowered, solitary or clustered, 

 discoid heads of purple, yellow or white, tubular, perfect and fertile, or rarely 

 dioecious flowers. Involucre ovoid or globose, its bracts prickle-tipped or un- 

 armed, imbricated in many series. Eeceptacle flat or convex, bristly. Corolla- 

 tube slender, the limb deeply 5-cleft. Filaments pilose, or rarely glabrous. 

 Anthers sagittate at the base. Style-branches short or elongated, obtuse. 

 Achenes obovate or oblong, compressed or obtusely 4-angled, glabrous, smooth 

 or ribbed. Pappus of several series of slender, plumose, bristles, connate at 

 the base. [Greek, the thistle was used as a remedy for swollen veins.] 

 Over 200 species, widely distributed in the northern hemisphere. Type species: 

 Carduus heterophyllus L. 



1. Cirsium Smallii Britton. 



Carduus pinetorum Small, Fl. SE. U. S. 1308, 1341. 1903. 



Cirsium pinetorum Small, Fl. Miami 199, 200. 1913. Not Greenm., 1905. 



Stem simple or little-branched, sparingly floccose, rather slender, 9 dm. 

 high or less. Leaves more or less floccose, runcinate-pinnatifid or entire, the 

 teeth and margins armed with yellowish acicular spine-like bristles 1.5 cm. 

 long or less; basal and lower leaves oblanceolate or spatulate-oblong, 1-2.5 dm. 



