OF ARTS AND SCIENCES. 175 
upward and subscabrous; cauline. leaves alternate, 2-24 inches in 
diameter, deeply 3-lobed, broadly cordate, scabrous above, pubes- 
cent beneath, lobes serrate, acuminate, the middle one more or less 
panduriform: petioles 9 lines long, winged: wings decurrent for 
some distance upon the stem: heads exclusive of the rays an inch 
in diameter: involucre hemispherical; bracts striate, with subfolia- 
ceous tips, the outer shorter, rounded at the apex, the inner equal- 
ling or slightly surpassing the disk, acute: rays about 8-10, deep 
yellow, 9 lines long; chaff scarious, carinate, very sharply acumi- 
nate, with or without lateral teeth: achenes 4-angled but decidedly 
compressed, narrowed downward, dark in color, often mottled with 
light red: pappus none or in the same head consisting of a ring 
of short unequal rather rigid teeth.— Las Palmas, San Luis Potosi, 
October, 1890 (n. 3675). This plant has so perfectly the habit 
and characters of a Tithonia that it should certainly be referred to 
this genus notwithstanding its short sometimes obsolete pappus. 
From T. tagetiflora, Desv., it differs in its involucre; from Z. di- 
versifolia, Gray, in its considerably smaller heads and shorter rays, 
as well as in achenes and pappus. 
VERBESINA Porosrna. Stem rather stout, furrowed, pubes- 
cent, leafy to the summit: leaves alternate, lance-oblong, attenu- 
ate, acute, sessile, auriculate, denticulate on the subrevolute edges, ee 
roughish pubescent above and finely dotted with the enlarged white © 
bases of the hairs; white tomentose beneath, less so on the veins: 
heads rather numerous, 5-6 lines in diameter, loosely corymbose, 
peduncles pubescent, 1-3 inches in length: scales of the involucre 
lanceolate, sharply acuminate, canescent, rather loosely imbricated, 
not equalling the disk flowers; rays about 12, very small, scarcely 
_ exceeding the involucre, yellow: disk strongly convex: chaff scari- 
ous, keeled, pubescent near the acuminate tips: disk flowers deep 
yellow: achenes oblanceolate, 1} lines in length, notched at the 
summit and with a slight angle on each face; wings moderately 
broad, upwardly ciliate, subacute above. — Mesas, Hacienda de An- = 
gostura, San Luis Potosi, July, 1891 (n. 5113). Near V. auricu- 
lata, DC. (ex char.), but differing in its radiate heads, narrower 
leaves, and lanceolate acuminate inyolueral scales. see 
Verpestya Prrveier. Fruticose: branches covered with a — 
whitish cortex; branchlets strongly angled, glabrous or nearly 802 
leaves opposite, lanceolate, attenuate, acute, rather coarsely and ae 
irregularly serrate-dentate, of harsh texture, scabrous above, i. 
bescent but scarcely rough beneath, 3-5 inches long, 1-1} Anches oo 
