24 PROCEEDINGS OF THE AMERICAN ACADEMY. 
with pale stipitate glands; involucre 8 to 10 mm. long; inner scales 
narrowly linear, attenuate, glandular, bristly chiefly near the midrib, 
scarcely at all woolly: achenes columnar, striate, reddish brown, 3 mm. 
long; pappus slightly tawny. —Jazisco: near Guadalajara, gravelly 
banks, Pringle, no. 5133 (hb. Gr.), hillsides, Pringle, no. 2990 (hb. Gr.), 
dry gravelly banks, Pringle, no. 4461 (hb. Gr.). Territory OF 
EPIC: between Dolores and Santa Gertrudis, Rose, no. 2044 (hb. U: S. 
Nat. Mus.). Starz or Mexico: Sierra de Ajusco, alt. 2440 m., Pringle, 
no. 7211 (hb. Gr.). 
Var, Ghiesbreghtii, n. var. Pedicels and involucral scales covered : 
with close wool (tawny in dried specimens) as well as stipitate glands: — 
habit, etc., of the typical form. — Curapas: growing in the plains, cool 
region, Ghiesbreght, no. 573 (hb. Gr.). 
Dovstrct Species. 
H. sturosum Fries. Leafy at base, the summit of the caudex 
woolly ; stem 1 to 1.2 dm. high, almost naked, branched, slightly sceab- 
rous: radical leaves densely rosulate, petiolate, lanceolate, repand- P 
dentate; the cauline reduced : inflorescence thyrsoidal, clothed with white 4 
floccose pubescence; involucre soft-villous : achenes narrowed down 
ward; pappus white. — Vet. Acad. Foérh. 1856, p- 146, & Epicris. 
Hierac. 148; Hemsl. Biol. Cent.-Am. Bot. ii. 260. — Mexico: 
Ehrenberg. A 
H. rricipum, Wedd. Chloris, And. i. 225 (1855) ; Klatt in Engl. 
Jahrb. viii. 52.— Klatt, 1. ¢., ascribes this South American spe- 
cies to Guatemala, a report based upon Lehmann’s no. 1526, which 
is not now in the Klatt Herbarium. No specimen from north of 
Panama has been seen by the writers, which corresponds with the 
South American plant. 
PSIS OF THE MEXICAN AND CENTRAL 
AMERICAN SPECIES OF ALNUS. 
By M. L. Ferraxp. 
3 _IV.—SYNO 
_ Severat Mexican | 
characters haye been 
and Central American Alders of very diverse 
qui generally called A, acuminata and A. jorullensts. 
This disposition of the forms has been most unsatisfactory, and the fol- 
o synopsis is offered as a partial solution of the difficulties presented 
