280 COMPOSITE. (composite family.) 



branching stems, and small heads of yellow flowers. (A name of Dioscorides for 

 some plant which exudes a gum.) 



1. C. juncea, L. Biennial, bristly-hairy below, smooth above (l°-3° 

 high) ; root-leaves runcinate ; stem-leaves few and small, linear ; heads scattered 

 on nearly leafless branches, 6" -8" long. — Fields and roadsides, abundant 

 near Alexandria, Virginia, M. J. Bebb, A.H. Curtiss; perhaps of recent intro- 

 duction. Aug. (Adv. from Eu.) 



81. PYRRHOPAPPUS, DC. False Dandelion. 



Heads, &c. nearly as in Taraxacum, but the soft pappus reddish or rusty- 

 color, and with a villous ring at the top of the long beak of the achenium. — 

 Mostly annual or biennial herbs, often branching and leafy below. Heads soli- 

 tary, terminating the naked summit of the stem or branches. Flowers deep 

 yellow. (Name composed of irvpp6s,Jiame-colored, and nannos, pappus.) 



1. P. CarolinianUS, DC. Stem branching (l°- 2° high); leaves oblong 

 or lanceolate, entire, cut, or pinnatifid, the stem-leaves partly clasping. — Sandy 

 fields, from Maryland southward. April- July. 



82. TARAXACUM, Haller. Dandelion. 



Head many-flowered. Involucre double, the outer of short scales ; the inner 

 of long linear scales, erect in a single row. Achenia terete, oblong, ribbed, and 

 roughened on the ribs, the apex prolonged into a very slender thread-like beak, 

 bearing the pappus of copious soft and white capillary bristles. — Perennials or 

 biennials, producing a tuft of pinnatifid or runcinate radical leaves, and slender 

 naked hollow scapes, bearing a single large head of yellow flowers. (Name 

 from rapaaaio, to disquiet or disorder, in allusion to medicinal properties.) 



1- T. Dens-lednis, Desf. (Common Dandelion.) Smooth, or at first 

 pubescent; outer involucre reflexed. — Pastures and fields everywhere: prob- 

 ably indigenous in the North. April - Sept. — After blossoming, the inner invo- 

 lucre closes, the slender beak elongates and raises up the pappus while the fruit 

 is forming ; the whole involucre is then reflexed, exposing to the wind the naked 

 fruits, with the pappus displayed in an open globular head. (Eu.) 



83. LACTUCA, Tourn. Lettuce. 



Heads several-flowered. Scales of the involucre imbricated in 2 or more sets 

 of unequal lengths. Achenia flat (compressed parallel to the scales of the invo- 

 lucre), abruptly contracted into a long thread-form beak, bearing a copious and 

 fugacious pappus of very soft and white capillary bristles. — Leafy-stemmed 

 herbs, with panicled heads ; the flowers of variable color, produced in summer 

 and autumn. (The ancient name of the Lettuce, L. sativa; from lac, milk, in 

 allusion to the milky juice.) 



1. L. Canadensis, L. (Wild Lettuce.) Biennial, mostly tall ; leaves 

 partly clasping, pale beneath ; the upper lanceolate and entire ; heads about 20- 

 flowercd ; achenia oval, rather longer than the beak, minutely rugose transversely 

 and roughish, one-ribbed on each face. The typical form (L. elongata, MM,, 



