528 PROCEEDINGS OF THE AMERICAN ACADEMY. 
opposite branches: leaves linear-oblong, entire, acute at each end, green 
on both sides, revolute at the margins, 3-nerved, thickish, scabrous, 1.4 
to 1.7 em. long, 2 to 4 mm. broad, puberulent under a lens: heads scat- 
tered, borne in the forks of the branches and terminally on short branch- 
lets: pedicels about 7 mm. long, appressed gray-pubescent : scales of the 
involucre ovate, narrowed to an obtusish or sometimes expanded and 
obtuse tip: rays about 6, light yellow, oblong, 8 mm. in length. — Du- 
rango, Mexico, 13 August, 1897, Dr. J. N. Rose, no. 2252. 
b. Leaves ovate. 
22. P. Menpezu, DC. Shrub, scabrous: leaves ovate-lanceolate, 
short-petioled, serrulate or nearly entire: heads numerous, on erect stiff- 
ish fastigiate pedicels: involucral scales in about 3 rows, the outer ovate, 
the inner oblong: rays “3 to 4” to 8.— Prodr. v. 608; Hemsl. l. ¢. 
182. — South Mexico at Villalpanda, Mendez. Type in herb. DC.; 
fragment in herb. Gray. To this species may be referred E. W. Nel- 
son’s no. 3433 from Chiapas, and Pringle’s no. 7610 from Hidalgo. 
Var. cylindrocephalum. Leaves lanceolate: involucre more cylin- 
drical; scales in 4 rows. — Mountain side near Cuernavaca, Morelos, 
altitute 2,500 m., C. G. Pringle, 22 May, 1898, no. 7658. Type in 
erb. Gray. 
++ +» Leaves and heads large, the latter rather crowded at the ends of the branches + 
inner scales of the involucre 8 to 12 mm. long. 
= Pubescence on branches and petioles fine, appressed : petioles not over 1 cm. 
in length. : 
23. P. Bertanpiert, DC. Leaves ovate, serrate or subentire, acute, 
rounded or scarcely cuneate at the base, 5 to 9 cm. long, obscurely pubes- 
cent: branchlets slender, nearly glabrous: rays 1 cm. long. — Prodr. V- 
608; Hemsl. 1. c. 181. — South Mexico, Guichilapa, Berlandier, 00- 
1040; also Valley of Mexico, Bourgeau, no. 964, and Mexico without 
locality, Schmitz. 
24. P. Klattii. Tall shrub (4 m. high) with spreading branches; 
branchlets thickish, silky-pubescent with appressed hairs: leaves ovate- 
lanceolate, acuminate at each end, finely gray-pubescent on both surfaces, 
crenate-serrate or subentire, large for the genus, 1.5 to 1.9 dm. long; 
6 to 7 em. broad: scales of the large involucre very broad and rounded 
at the summit; rays 12, oblong-lanceolate, 1.8 cm. long. — P. g” ande, 
Ratt in Engl. Jahrb. viii. 43, not Hemsl.— On the Rio Risasalda, Cauc@, 
U. S. Colombia, altitude 1,400 to 1,800 m., 24 November, 1883, F. ©: 
Lehmann, no. 3282. Type in herb. Gray. 
