Subtribe 3. Tarchonantheje, Less.—Heads discoid, never radiate, dioecious
or heterogamous ; tbe fertile flowers tubular-filiform, mostly truncate,
when heterogamous with the perfect or staminate flowers in the centre.
Receptacle sometimes chaffy. Anthers caudate at the base.—Leaves
alternate.
CONSPECTUS OF THE GENERA.
* Pappus o f the sterile and fertile flowers similar, capillary.
58. P lochea. Involucre persistent. Heads in compound corymbs.
59. P terocaulon. Involucre deciduous. Heads spicate. Leaves decurrent.
* * Pappas o f the sterile and fertile flowers none. Receptacle fla t or conical.
+- Flowers all fertile.
60. C alymmandra. Achenia of the perfect flowers only enclosed by the chaff.
+- +- Staminate flowers few, sterile.
61. F ilaginopsis. Fertile flowers numerous, in the axils of narrow equal chaff.
62. D iaperia. Fertile flowers 8-12, in the axils of broad unequal concave chaff.
53. M icropus. Fertile flowers 5-7, enclosed in rigid gibbous scales.
64. PsiLocARPHtrs. Fertile flowers numerous, enclosed in membranous chaff.
* * * Pappus o f the sterile flowers o f few bristles. Receptacle columnar.
65. Stylocline. Achenia numerous, enclosed in the saccate keel of the broad
chaff.
58. PLUCHEA. Cass. bull, philom. 1817, p. 31 ; DC. prodr. 5. p . 449.
Stylimnus Sc Gynema, Raf. (1819.)—Leptogyne, Ell. (1824.)
Heads many-flowered; the central flowers mostly perfect, but sterile ; the
others filiform, pistillate, in many series. Involucre imbricated. Receptacle
flat, mostly naked. Corolla of the fertile flowers truncate, or minutely
2—3-toothed; of the sterile dilated and 5-cleft at the summit. Anthers
bicaudate. Style in the central flowers entire or minutely 2-toothed. Achenia
somewhat cylindrical, angled or grooved. Pappus capillary, in a single
series, slightly scabrous.—Herbs, or rarely suffrutescent plants (mostly subtropical),
glandular, emitting a strong and somewhat disagreeable odor.
Leaves oval or oblong, serrate. Heads in compound corymbs. Flowers
mostly purplish.
1. P. bifrons (DC.): pubescent and slightly viscid; leaves oval or lanceolate
oblong, somewhat cordate and clasping at the base, mucronately serrulate,
reticulate-veined, sprinkled with resinous globules; heads in compact
fastigiate corymbs.—DC.! prodr. 5. p. 451. Conyza bifrons, Linn. spec. 2.
p . 862 (excl. var. radiata); Pursh, fl. 2. p. 524 ; Ell. sk. 2. p. 322; Hook,
compan. to bot. mag. 1. p. 96. C. amplexicaulis, Michx.! fl. 2. p. 126.
/3. uliginosa, Pers., ex DC. Baccharis visco3a, Walt. ! car. p. 202.
Wet places in the low country, from South Carolina! to Florida! and
Louisiana! July .-Sept.— 11 Stem 2-3 feet high. Leaves 2-3 inches
long, rather acute. Flowers dull purple.
2. P. fcetida (DC.): stem minutely pubescent; leaves (large) oval-lanceolate,
very acute or acuminate, at each end, distinctly petioled, membranaceous,
almost glabrous, conspicuously feather-veined, serrate ; corymbs compound,
paniculate; scales of the involucre glabrous, dotted with minute
glands.—DC.! prodr. 5. p. 452. (excl. syn. Pursh Cass.?) P. petiolata,
Cass, in diet. sci. nat. 42. p. 2? Baccharis fcetida, Linn. spec. 2. p. 861, at
least as to syn. Dill. EUh. t. 89, ƒ. 105. Conyza camphorata, Pursh, fl: 2.
p. 523; Nutt. gen. 2. p. 145, not of Ell.? nor Erigeron camphoratum, Linn.
Gynema dentata & viscida, R a f.! ann. nat. p. 159 &f in herb. DC.
Along streams, &c. Pennsylvania? to Alabama! and throughout the
Western States ! Aug.-Oct.— 11 Stem strongly grooved or angled, 2-4 feet
high : the plant exhaling a more powerful odor than the following species.
Leaves 5-8 inches long, and 1-3 broad, pubescent beneath, especially on the
veins, and copiously sprinkled with minute resinous globules, very veiny.
Heads numerous : the involucre at first rather longer than the disk.—We
are somewhat uncertain as to the plant of Clayton on which the Baccharis
fcetida of Linnaeus was partly founded ; but the figure of Dillenius here cited
doubtless was intended for this species. The Erigeron camphoratum, Linn,
hort. Ups. &(c. is pretty clearly the following. We therefore retain the synonymy
of De Candolle, but reduce two of his species to one.
3. P. camphorata (DC.): minutely viscid-pubescent and glandular; leaves
lanceolate-ovatemr oblong-ovate, serrile or slightly petioled, pale and minutely
pubescent and sprinkled-with resinous globules'both sides, slightly
feather-veined, repandly serrate ; corymbs fastigiate; scales of the involucre
pubescent and viscid, ciliate.—P. camphorata & P. Marilandica, DC.! 1. c.
P. Marilandica, Cass. 1. c. ? Erigeron camphoratum, Linn. spec. 2. p. 864 ,*
Willd.! spec. 3. p. 1960. Conyza Marilandica, (Dill. Elth. t. 88, f. 104 ?)
Michx.! fl. 2. p. 126; Pursh! 1. c .; Nutt. 1. c .; Ell. sk. 2. p. 320. C.
camphorata, (Ell. 1. c. ?) Bigel. fl. Bost, ed. 2. p. 299, not of Pursh, 8fc.
Baccharis fcetida, Walt. ? Stylimnus.maritimus, R a f.! in herb. DC.
ft. angustifolia: leaves lanceolate, obscurely serrulate or entire.—Conyza
angustifolia, Nutt.! in jour. acad. Philad. 7. p. 109.
Salt marshes, Massachusetts! to Florida! and Louisiana! Aug.-Oct.—
(1) Stem 10-30 inches high. Leaves slightly succulent, 2-3 inches long.
Heads fewer and larger than in the preceding; the purplish involucre at
length shorter than the disk. Flowers light purple.
4. P. purpurascens (DC.): herbaceous, somewhat viscidly puberulent;
leaves ovate-lanceolate, rather acute, unequally serrate, tapering into a petiole,
minutely puberulent and glandular, somewhat veiny; heads subglobose,
pedicellate, in loose corymbs; scales of the involucre pubescent-tomentose
and viscid; the exterior ovate, the inner oval-lanceolate, somewhat spreading.
DC. prodr. 5. p. 452.—Conyza purpurascens, Swartz, prodr. Ind.
Occ. p. 112 ?
Key West, Mr. Blodgett!—Apparently a rather small annual herb; with
much the habit and appearance of C. camphorata, the leaves about the same
size, but narrower; the oauline ones tapering into distinct petioles. As we
have seen specimens of the same species from St. Domingo, we have little
doubt that it is De Candolle’s P. purpurascens, and most probably his P.
glabrata also.
Conyza Caroliniensis of Jacquin is referred by De Candolle to Pluchea (Conyza,
IAv/n.) odorata, a shrubby West Indian and Mexican, but certainly not a Carolinian
species.