432 
Bentham relegated it to the second, as a species of Eupatorium. 
With none of the 6 genera of this first section does it agree. It 
appears to belong between (64) Agrianthus and (65) Symphyopap- 
pus, both Brazilian genera. Its most distinct characters are its 
spine-tipped involucral scales in 4 strictly vertical ranks, giving a 
perfectly regular quadrangularly prismatic involucre, and the very 
unequal rigid purple seta of the pappus. 
ADDISONIA. 
Head homogamous, tubuliflorate and panciflorate. Involucre 
narrow, prismatic-quadrangular; scales about 12 to 14, in 4 vertical 
ranks, the outer successively shorter, the outermost very small, 
rigid, roughened, strongly keeled, produced into a spine-like tip. 
Receptacle naked, elevated and prominent as an irregularly and 
sharply angled body. Corollas equal, tubular, the limb campanu- 
late, its border spreading, strongly 5-toothed. Anthers with 
obtuse triangular appendages and obtuse, nearly entire bases. 
Style-branches' long, much exserted, obtuse, distinctly dilated 
upward, papillose. Achenia sharply 5-angled. Pappus wholly of 
sete in a single series, easily detached altogether with the disc, 
25-30, very unequal, rigid, stout, purple, moderately barbellate. 
A tough (glutinous?) shrub, with elongated, appressed, erect- 
spreading branches; alternate, sessile, very small, linear spatulate, 
fleshy, papillose leaves, and heads solitary at the ends of abbre- 
viated leafy branchlets, these crowded at the ends of the branches. 
The involucre, rigid, purple pappus and corolla characters are 
suggestive of Svevia, while the general habit is that of Ageratella. 
Specimens of the same plant, collected by Pearce, in the Kew 
herbarium are marked by Mr. Bentham “ Zupatorium,’ but no 
species is named. 
Genus dedicated to the honored President of the Torrey Bo- 
tanical Club, Judge Addison Brown. 
A. vircata. Branches very slender, bright brown, slightly chan- 
~ nelled, the internodes shorter than the leaves; leaves 5—I2 
mm. long, I-2 mm. broad, linear-spatulate, below narrowed to 
a petiole-like base, obtusish, very thick, grayish-green, papil- 
lose with prominent broad midrib; heads virgately racemed 
and somewhat secund, at maturity 9 mm. long, 3—3.5 mm. 
broad. Involucre 6-7 mm. long by 3 mm. broad, regularly 
tapering to an acute base; the scales rigid, lanceolate boat- 
shaped, above keeled, with scarious spreading margins and 
pungently tapering apex, finely several-nerved, papillose; 
flowers about 5; corolla dull yellowish-white, 5 mm. long, 5- 
toothed, the teeth spreading, acutish; pappus bright purple, 
