226 COMPOSITE. Pludusa. 



one of De Candolle's, which continues the principal Linnasau specific name, is to 

 be preferred. Conyza Carolinensis, Jacq., is Pluchea odorata, wrongly attrib- 

 uted to Carolina. 



P. bifroilS, DC. Stems nearly simple, 2 or 3 feet high from a perennial root: leaves veiny, 

 acutely denticulate, from oblong to lanceolate, commonly obtuse at both ends (2 to 4 inches 

 long), partly clasping or closely aduate-sessile : heads glomerate in leafy-bracted sessile 

 clusters : iuvolucral bracts lanceolate. Prodr. 1. c. ; Torr. & Gray, Fl. ii. 260, excl. syu. L. ! 

 Baccharis fat/da, L. Spec. 801, as to pi. Grouov. B. viscosa, Walt. Car. 202. Conyza 

 lifrons, Pnrsh, Ell. 1. c., &c., not L. C. ample xicaulis, Michx. Fl. ii. 126. C. uliginosa, Pers. 

 Syn. ii- 427. Wet soil, Cape May, New Jersey, and through the low country to Keys of 

 Florida (where is a very narrow-leaved variety, Conyza angiistlfolia, Nutt. Jour. Acad. 

 Philad. vii. 109 1), and Texas. ( W. Ind.) 



P. camphorata, DC. Stems 2 to 5 feet high from an annual (not perennial) root: leaves 

 from oblong-ovate to oblong-lanceolate, acute or acuminate at both ends, denticulate or den- 

 tate (3 to 8 inches long), the larger distinctly or indistinctly petioled; primary veins often 

 evident, but veiulets obscure : heads numerous and crowded in naked convex or corymbiform 

 cymes, commonly short-pedicelled : iuvolucral bracts from ovate to lanceolate, often tinged 

 with purple. Erigeron camphoratum, L. Spec. ed. 2, 1212 (Gronov. Virg. ed. 1, 96, Clayt. 

 no. 165). Baccharis fcetida, L. Spec. ed. 1, 861, as to syn. Dill., not as to Gronov. Conyza 

 Marilandica, etc., Dill. Elth. t. 88, fig. 104, & C. Americana frutescens, etc., Dill. 1. c. t. 89. 

 C. Man/landica, Michx. 1. c. C. Marilandica & C. camphorata, Pursh, Fl. ii. 523 ; Ell. 1. c. 

 Gi/nema de.nt.ula, viscida, &c., Raf. Ann. Nat. 159. Pluchea Marilandica & P. petiolata,' 

 Cass. Diet. I.e. P. Marilandica, foetida, camphorata, also (W. Ind.) P. purpurascens & P. 

 glabrata? DC. 1. c. P. fcetida, camphorata, & purpurascens, Torr. & Gray, Fl. ii. 261. Salt 

 marshes and moist saline soil, Mass, to Florida, Texas, Arizona, and coast of California: in 

 shady places or less saline soil, with leaves thinner and more petioled, and involucre almost 

 glabrous, when it is P. petiolata, Cass. (Adj. Mex., W. Ind.) 



53. PTEROCAtTLON, Ell. BLACK-ROOT. (nrepoV, wing, and 

 stem.) -- Mostly perennial herbs, the typical species American; with one excep- 

 tion all tomentose-canescent except the upper face of the sessile pinnately veined 

 leaves, these decurrent on the whole stem, forming wings ; small sessile heads 

 spicate at the summit of the stem and virgate branches ; the flowers usually white 

 or whitish, in summer. --E11. Sk. ii. 323 ; DC. Prodr. v. 453. Chlcenobolus, Cass. 

 Diet. Sci. Nat. xlix. 348. 



P. pycnostachyum, ELL. 1. c. Roots fasciculate and tuber-like or fusiform, black : stem 

 2 feet high, mostly simple : leaves from oblong to lanceolate, minutely denticulate : heads 

 crowded in a dense and continuous spiciform naked thyrsus (of 3 to 8 inches in length) : in- 

 volucre lauate-tomeutose. Torr. & Gray, Fl. ii. 262. Conyza pycnostacliya, Michx. Fl. 

 ii. 126. CitiULiiobolus pycnostachijus, Cass. 1. c. Gnaphalium undulatum, Walt. Car. 203. 

 Dry pine barrens, near the coast, N. Carolina to Florida. 



P. virgatum, DC. Root fusiform and fibrose (perhaps biennial) : stem slender, simple or 

 with virgate branches : leaves linear and very acute, entire, or the lower caulinc lanceolate 

 and obscurely serrulate, the venation hardly apparent : heads narrow, in separated glomer- 

 ules ; these forming a virgate and elongated interrupted spike-like inflorescence : involucre 

 appressed-tomentose, or the subulate inner bracts glabrate. Prodr. v. 454. Gnaphalium 

 riri/tiiiun, L. Amain. Acad. v. 405. Conyza vinjata, L. Spec. ed. 2, 1206, with syn. 

 < lilamobolus virgatus, Cass. I.e. Open pine woods near Houston, Texas, Lindheimer. (W. 

 Ind., Mex.) 



54. MlCROPUS, L. (MIK/JO'S, small, TTO??, foot, the soft-woolly small 

 heads or clusters like Leontopodium, or Lion's-foot, on a small scale.) Low 

 floccose-woolly annuals, with alternate entire leaves, belonging to the Old World, 

 except our Pacific coast species. Gaertn. Fr. t. 164; Schkuhr, Handb. t. 267; 



