FiLAGo. COMPOSITE. 399 



37. FILAGO. Tourn. ; DC. prodr. 6. p. 247. COTTON ROSE. 



[ From ihe Latin, JUum, a thread ; the plant being covered with fine cobweb-like threads.] 



Heads many-flowered, heterogamous ; the central flowers tubular, 4 - 5-toothed, perfect, but 

 often infertile; the others pistillate, filiform. Scales of the involucre few, the exterior 

 mostly woolly. Receptacle elongated or turbinate, chaffy at the base, naked at the summit. 

 Pappus of the central flowers capillary ; of the exterior caducous or none. Achenia nearly 

 terete. — Annual woolly herbs, usually branched. Leaves alternate, entire. Heads glome- 

 rate or fascicled. 



1. FiLAGO Germanica, Linn. Herha Impia. 



Stems dichotomous ; the branches arising from the base of the capitate glomerules ; leaves 

 lanceolate, acute ; heads pyramidal ; involucral scales cuspidate ; the exterior pistillate flowers 

 in several series, destitute of pappus. — Linn. sp. ed. 2. p. 1311 ; DC. prodr. 6. p. 247 ; 

 Torr. <^ Gr. fl. N. Am. 2. p. 432. Gnaphalium Germanicum, Linn. sp. (ed. 1.) 2. p. 857; 

 Engl. hot. t. 2369 ; Pursh, fl. 2. p. 526 ; Torr. compend. p. 289 ; Beck, bat. p. 178 ; Dar- 

 lingt. fl. Cest. p. 493. 



Stem 3-8 inches high, at first simple and bearing a terminal cluster of heads, but at length 

 more or less branched, clothed (like the leaves) with a woolly tomentum. Leaves about 

 three-fourths of an inch long, numerous, erect. Heads crowded in small roundish or ovoid 

 clusters. Scales of the involucre straw-colored or tawny. Receptacle small, turbinate, 

 tuberculate. Achenia minutely papillose. 



Dry fields and sterile hill-sides. Staten Island. August - September. Introduced from 

 Europe. 



Subtribe VI. Senecione^, Cass. Heads homogamous or heterogamous, never dioecious, 

 discoid or radiate ; the rays ligulate, in a single series. Receptacle scarcely ever chaffy. 

 Anthers not caudate. Pappus capillary, rarely wanting in the exterior flowers. 



CONSPECTUS OF THE GENERA. 

 * Heads discoid^ heterogamous ; the JUnaers all tubular. 



38. Ebechtites. Marginal flowers pistillate, very slender, 2 - 3-toothed. 



•* Heads homogamcfus, or heterogamous and radiate. 



39. Cacalia. Heads discoid, 5 - many-flowered. Achenia smooth. Pappus rough. Flowers white or whitish. — 



Leaves alternate. 



40. Senecio. Heads radiate or discoid, many-flowered. Pappus of very slender bristles. Receptacle flat or convex. 



Flowers mostly yellow. — Leaves alternate. 



41. Abnica. Heads radiate, many-flowered. Pappus barbellate or strongly denticulate, rather r.gid. Receptacle flat. 



— Leaves opposite. 



