60 Contributions from the Gray Herbarium 
typica V. hypargyrea Greenm. — Three species of northern Mexico, 
with few or solitary large heads and sessile alternate lanceolate or 
lance-ovate leaves which are silky or tomentose beneath. 
a. Leaves strongly GOOORORE as es Oe . 13. V. decurrens. 
4. V. Roset. 
b. Stem merely pilose-strigose; leaves 4-7.4 em. long. ...15. V. hypargyrea. 
13. V. DECURRENS Gray. Stout erect herb, 0.6—-1 m. high, very 
leafy. Stem simple, 1—4-headed, pilose-tomentose, angulate. 
Leaves alternate, ovate to oblong-ovate, acuminate, narrowed to 
the base and very strongly decurrent on the stem, green and rather 
softly tuberculate-hispidulous above, pale, glandular, and canes- 
cent-pilose beneath with appressed hairs, 1-nerved and feather- 
veined (the veins uniting to form a submarginal nerve), 11-19 em. 
long, 2.4-6 cm. wide. Heads 5-6 cm. wide, on pilose often winged 
peduncles, these 1-10.5 em. long, not at all or only slightly thick- 
ened at apex; disk 1.6—(fruit)2.7 em. high, 3-4 em. thick. In- 
volucre 2(—3)-seriate, subequal or with the outer phyllaries longer 
and exceeding the disk, 11-22.5 mm. high, the phyllaries oblong or 
broadly oblong-ovate, subacute, at first canescent-pilose, in fruit 
thickened, ribbed, and subglabrate below, the triangular subher- 
baceous apex loosely spreading or reflexed. Rays about 14, 1.4- 
2 cm. long, 3.5-4.5 mm. wide; disk-corollas glandular and ap- 
pressed-pilose, 6—(fruit)8.5 mm. long (tube 1-1.7 mm.). Pales 
truncate, 1.2 em. long or more. Achenes 7 mm. long, densely 
appressed-pubescent. Awns 4.5 mm. long; squamellae united at 
very base, about 6-10, lacerate, unequal, up to 1.6 mm. long. — 
Gray! Proc. Am. Acad. xix. 5 (1883). Tithonia decurrens Gray! 
Pl. Fendl. 85 (1849). 7. recurrens Hemsl. Biol. Centr.-Am. Bot. 
N. 176 (1881), sphalm. — MEXICO: CHIHUAHUA: common on 
mountains around Cosiquiriachi, Oct. 1846, Wislizenus 193 (TPE: 
G.); grassy slopes, Santa Eulalia Mts., 9 Sept. 1885, Pringle 676 
(BMG, Kv. S.); mountains near Chihuahua, 29 Sept. 1886, 
Pringle 1063 (Mo.); Sierra Madre near Colonia Garcia, 2385 m., 
25 Aug. 1899, Townsend & Barber 279 (B. Ps G., Ki; Mo., U8): 
Marsh Lake, Sierra Madre, 2135 m., 19 Sept. 1903, M. E. Jones 
(U. 8.); Sierra Madre, 25 Aug. 1899, E. W. Nelson 6287 (G., 
U8.); Guajochiec, 8 Sept. 1892, Hartman 562 (G.); Colonia 
Juarez, 1585 m., Sept. 1903, ML, Jones (Mo.); Durango: rocky 
