Genus 15. 



CHICORY FAMILY. 



>'S 



15. LEONTODON L. Sp. PL 798. 1753. 

 [Taraxacum (Hall.) Ludwig, Def. 175. 1760.] 

 Perennial acaulescent herbs, with basal tufted pinnatifid or sinuate-dentate leaves, and 

 large heads of yellow flowers, solitary, or very rarely 2 or 3 together at the ends of naked 

 hollow scapes. Involucre oblong or campanulate, its inner bracts in 1 series, nearly equal, 

 slightly united at the base, the outer of several series of shorter somewhat spreading ones, 

 often reflexed at maturity. Receptacle flat, naked. Rays truncate and 5-toothed at the summit. 

 Anthers sagittate at the base. Style-branche6 slender, obtusish. Achenes oblong or linear- 

 fusiform, 4-5-angled, 5-10-nerved, roughened or spinulose, at least above, tapering into a 

 very slender beak. Pappus of numerous filiform unequal simple persistent bristles. [Greek, 

 lion's-tooth.] 



About 20 species, natives of the northern hemisphere and southern South America. Type 

 species : Leontodon Taraxacum L. 



Outer involucral bracts reflexed ; achenes greenish brown, the beak 2-3 times their length. 



1. L. Taraxacum. 

 Outer involucral bracts spreading or ascending. 



Achenes greenish, the beak 2-3 times their length. 2. L. latilobum. 



Achenes red, the beak not more than twice their length. 3. L. erythrospermum. 



i. Leontodon Taraxacum L. Dandelion. Blowball. Fig. 4062. 



Leontodon Taraxacum L. Sp. PI. 798. 1753. 

 T. officinale Weber, Prim. PI. Hoist. 56. 1780. 

 T. Dens-leonis Desf. Fl. Atlant. 2: 228. 1800. 

 T. Taraxacum Karst. Deutsch. Fl. 1138. 1880-83. 



Root thick, deep, often 10' long, bitter. Leaves 

 oblong to spatulate in outline, usually pubes- 

 cent, at least when young, acute or obtuse, 

 pinnatifid, sinuate-dentate or rarely nearly 

 entire, rather succulent, 3'-lo' long, i'-2i' wide, 

 narrowed into petioles; scape erect, 2-18' high ; 

 head I '-2' broad; containing very numerous 

 golden-yellow flowers (150-200), inner bracts 

 of the involucre linear or linear-lanceolate, the 

 outer similar, shorter, not glaucous, reflexed, 

 all acute; achenes greenish-brown, fusiform, 

 spinulose above, narrowed into a filiform beak 

 2-3 times their length, which support the 

 copious white pappus, the fruiting mass of 

 which becomes globose when ripe. 



In fields and waste places, naturalized as a 

 weed from Europe. Also in Asia and distributed 

 as a weed in all civilized parts of the world. Jan.- 

 Dec. Called also lion's-tooth, cankerwort, milk- 

 witch- or yellow-gowan, Irish daisy, monk's-head, 

 priest's-crown, puff-ball. Arnica. 



2. Leontodon latilobum ( DC. ) Britton. 

 Mountain Dandelion. Fig. 4063. 



Taraxacum latilobum DC. Prodr. 7: 146. 183S. 



T. Taraxacum alpinum Porter, Mem. Torr. Club 

 5: 349. 1894. 



Similar to the preceding but scape lower. 

 2'-y' high. Leaves sinuately lobed with broadly 

 triangular lobes, but less deeply so than in 

 L. Taraxacum and rarely as far as half way 

 to the midrib, or often merely dentate or sub- 

 entire; heads smaller, or about 1' wide; bracts 

 fewer, the outer broadly ovate, appressed or 

 merely spreading. 



In moist places, Newfoundland and Labrador 

 to Quebec. Europe. Summer. Rocky Mountain 

 and northwestern plants formerly regarded as 

 included in this species are now considered dis- 

 tinct. 



