BRAUNERIA CARDUUS 263 



( 1 ) Leaf-segments linear ; achenes 2-awned B. tenuisecta 



(2) Leaf-segments triangular to oblong; 



achenes 3-4-awned B. bipinndta 



BRAUNERIA Necker 1790 

 (Named for Brauner, a German botanist) 



Heads with pink to rose-purple neutral rays, disk-flowers perfect, 

 brown, achenes 4-sided, pappus a crown of teeth ; receptacle conic, with 

 stiff pointed chaff, involucre hemispheric, the bracts imbricated in 2-4 rows ; 

 heads solitary on long stalks; leaves alternate or opposite, entire or 

 toothed; perennial. 

 Stems bristly, 1-3 ft. high ; leaves lanceolate, 3-8 in. 



long; rays 10-20, 1-2.5 in. long B.pdllida 



CARDUUS Linne 1753 THISTLE 



(The Latin name of the thistle) 



PI. 37, fig. 6. 



Heads without rays, rarely dioecious, disk-flowers with long, deeply- 

 cleft corolla tube, perfect as a rule, achenes oblong to obovate, flattened or 

 4-angled, pappus of several rows of hair-like bristles; receptacle flat or 

 convex, bristly, involucre ovoid to globose, the bracts usually imbricated in 

 many rows and spiny-tipped; heads large, solitary or clustered; leaves 

 alternate or basal, toothed to pinnatifid, usually spiny ; biennial or perennial. 

 1. Heads 1.5-3 in. high, perfect 



a. All the bracts, or at least the inner ones, with 



broadened fringed tips ; flowers yellow or 

 yellowish 



(1) All the bracts with broadened fringed tips, 



not cobwebby, the spines short or none ; 



leaves green above, white-felted below C. americdnus 



(2) Inner bracts with broadened fringed tips, 



outer with spines -5-10 mm. long 



(a) Leaves green and smooth when mature, 



oblong-ovate ; bracts cobwebby C. Pdrryi 



(b) Leaves green and hairy or white below, 



long and narrow ; bracts not cobwebby C. Drummondii 



b. None of the bracts with broadened fringed 



tips ; white, yellow or purple 

 (1) Bracts without a sticky ridge or line on the 

 back 



