COMPOSITAE. 973 



spatulate, erect or ascending, obtuse or acutish, 6-25 mm. long , atem terminated 

 by a sessile dense cluster of heads, usually subtended by several leafy branches 

 terminated by similar clusters and these often again proliferous; heads 10-30 in 

 each cluster, many-flowered; involucre ovoid, light yellow, its bracts mainly acute. 

 In dry fields, southern N. Y. to Penn. and N. Car. May-Sept. 



42. PLUCHEA Cass. 



Pubescent or glabrous herbs, or some tropical species shrubby, with alternate 

 dentate leaves, and small heads of tubular flowers in terminal corymbose cymes. 

 Involucre ovoid, campanulate, or nearly hemispheric, its bracts appressed, herba- 

 ceous, imbricated in several series. Receptacle flat, naked. Outer flowers of the 

 head pistillate, their corollas filiform, 3-cleft or dentate at the apex. Central flow- 

 ers perfect, but mainly sterile, their corollas 5-cleft. Anthers sagittate at the base, 

 the auricles caudate. Style of the perfect flowers 2-cleft or undivided. Achenes 

 4-5 angled. Pappus a single series of capillary scabrous bristles. [Named for the 

 Abbe N. A. Pluche, of Paris.] About 30 species, widely distributed in warm and 

 temperate regions. 



Perennial: leaves sessile, cordate, or clasping at the base. I. P.foetida. 



Annual; leaves, at least those of the stem, petioled. 



Leaves short-petioled ; heads about 6 mm. high; involucral bracts densely puber- 

 ulent. 2. P. camphorata. 



Leaves long-petioled; heads 4-5 mrn. high; involucral bracts granulose, ciliate. 



3. P. petiolata. 



1. Pluchea foetida (L.) B.S.P. VISCID MARSH FLEABANE. (I. F. f. 3839.) 



Stem simple or sparingly branched at the summit, puberulent and slightly viscid, 

 4-9 dm. high. Leaves oblong, ovate or ovate-lanceolate, sharply denticulate, 

 pubescent or puberulent, 510 cm. long, 14 cm. wide, reticulate-veiny ; clusters 

 of heads compact, leafy-bracted ; involucre 5-6 mm. high, its bracts lanceolate, 

 acute, viscid-puberulent. In swamps, southern N. J. to Fla. and Tex., mainly near 

 the coast. Also in the W. Ind. July- Sept. {Pluchea bifrons DC.] 



2. Pluchea camphorata (L.) DC. SPICY OR SALT-MARSH FLEABANE. (I F. f. 

 3840. ) Stem usually branched, finely viscid-puberulent, or nearly glabrous, 6-9 

 dm. high, somewhat channeled. Leaves ovate, oblong or lanceolate, puberulent or 

 glabrous, acute or acuminate at the apex, narrowed at the base, the upper sessile 

 but not clasping, 7-20 cm. long, 3-7 cm. wide, serrate or denticulate, not conspicu- 

 ously reticulate-veined; bracts of the involucre ovate-lanceolate, or lanceolate, 

 acute; flowers purplish; achenes pubescent. In salt marshes, coast of N. H. to Fla., 

 Tex. and Mex. Also in the \V. Ind. Aug. -Oct. 



3. Pluchea petiolata Cass. INLAND MARSH FLEABANE. (I. F. f. 3841.) 

 Similar to the preceding species, but glabrate, usually taller, 7-12 dm. high, the 

 stem stout, rather strongly channeled. Leaves ovate-lanceolate to oval, thin, 10-25 

 cm. long, 4-7 cm. wide, mostly acuminate at the apex, cuneate narrowed at the 

 base, irregularly serrate; petioles of the larger leaves 15-25 mm. long; achenes 

 short-pubescent. In moist soil, often in woods, Va. to Fla., 111., Mo. and the Ind. 

 Terr. Aug. -Oct. 



43. ANTENNARIA Gaertn. (See Appendix.) 



Perennial woolly dioecious or polygamo-dicecious herbs, with alternate and 

 basal leaves, and small discoid many-flowered heads, glomerate, racemose, solitary, 

 or corymbose. Involucre oblong, ovoid or campanulate, its bracts scarious, imbricated 

 in several series, the outer shorter, usually woolly. Receptacle convex, or nearly 

 flat, foveolate, not chaffy. Staminate flowers with a truncate or minutely dentate 

 corolla, usually undivided style and scanty pappus of club-shaped smooth or 

 minutely barbed bristles. Pistillate or perfect flowers with tubular mostly 5 -toothed 

 corollas, 2-cleft style, and copious pappus of capillary naked bristles, slightly 

 united at the base. Achenes oblong, terete, or slightly compressed. [Latin, in 

 allusion to the fancied resemblance of the sterile pappus to insect antennae. ] About 

 50 species, natives of the north temperate zone and southern S. Am. In addition 

 to the following, about a dozen, others occur in the western parts of N. Am., and 

 one or more in the Southern States. 



