258 COMPOSITE FAMILY. 



Ing into 2-7 slender peduncles bearing small about 20-flowered heads ; 

 akenes linear. X., S. to Ga. 



H. 8c4brum, Miclix. Uoughish-hairy, with rather stout simple stem 

 (2°-3° high), bearing obovate or oval nearly entire leaves, and a narrow 

 panicle of many small heads, the 40-50-tlowered involucre and stiff 

 peduncles thickly beset with dark glandular bristles. N., S. to Ga. 



■w- t-1- Akenes tapering at the top ; panicle narrow or virgate. 



H. longlpilum, Torr. So named from the exceedingly long (often 1') 

 straight bristly hairs of the stem ; leaves narrow-oblong, entire ; panicle 

 and 20-30-flowered involucre between the last and the next. Mich., W. 

 and S. 



H. Gron6vii, Linn. Stems slender, leafy, and very hairy below ; 

 leaves oblong or obovate ; heads small ; slender peduncles and 20-30- 

 flowered involucre sparingly glandular-bristly. N. and S. 



75. PRENANTHES (or NAB ALUS), RATTLESNAKE ROOT. 

 (Greek: drooping blossom.) 



* Peduncles and l2-40-flowered heads hairy. 



P. racem6sa, Michx. Smooth wand-like stem 2°-5° high ; leaves 

 lance-oblong, slightly toothed, the upper ones partly clasping; narrow 

 spiked panicle of about 12-flowered heads. N. 



P. aspera, Michx. Similar, but rough-pubescent, the upper leaves 

 not clasping and the 12-14-flowered heads mostly erect and larger. Ohio, 

 W. and S. 



P. crepidinea, Michx. Smoother, with stout stem 6°-8° high, wide- 

 corymbed panicles of 20-40-flowered heads, brown pappus, and broad 

 leaves 6'-12' long on winged petioles. Penn., W. and S. 



* * Peduncles and 6-\2-flowered heads smooth ; leaves very variable. 



P. altissima, Linn. Tall R. or White Lettdce. Rich woods N., 

 3o_60 high, with long and narrow leafy panicle, petioled leaves inclined 

 to be ovate-triangular ; heads 5-6-flowered ; pappus dirty white. 



P. ilba, Linn. Common White Lettuce, in open woods, chiefly N. 

 and W. ; glaucous, with more coryinbed panicles of 8-12-flowered heads, 

 usually more cut or divided leaves, and cinnamon-colored pappus. 



P. serpentaria, Pursh. Lion's Foot, or Gall of the Earth. Com- 

 monest in dry soU E. and S. ; l°-4° high, with narrow-corymbed panicles 

 of 8-12-flowered heads, and pappus dull straw-color. 



76. PYRRHOPAPPUS, FALSE DANDELION. (Greek: flame- 

 colored pappus; this and the leafy stems distinguish this genus from 

 the next.) (g) 



P. CaroliniinuB, DC. l°-2° high, with oblong or lanceolate leaves 

 often pinnatifid or cut, the upper partly clasping ; flowers spring and 

 summer. Sandy fields from Md., S. 



77. TARAXACUM, DANDELION. (Greek name referring to medici- 

 nal properties of the root.) @ H (Lessons, Fig. 384.) 



T. officinale, Weber. Common D. In all fields, from spring to autumn. 

 Inner involucre closes after blossoming till the akenes mature and the 

 beak lengthens and elevates the pappus ; then the involucre is reflexed, 

 the pappus spreads, and with the fruit is blown away by the wind. Very 

 variable. Eu, 



