ROBINSON AND GREENMAN. — HIERACIUM. 15 
from some recently secured tracings and fragments of Lessing’s species 
preserved in the Royal Botanical Museum, at Berlin. From these new 
sources and a very full suite of excellent modern specimens collected by 
Messrs. Pringle, Palmer, Nelson, L. C. Smith, Conzatti, Gonzalez, Rose, 
Pittier, Brandegee, and others, it is now possible to offer the following 
synopsis with a reasonable confidence that it will prove a useful basis for 
further work in its particular field. For the sake of comparison a few 
species, which are at present known only in the southwestern United 
States but are likely to extend within the boundaries of Mexico, are 
here included. 
HIERACIUM, Tourn. (Name from iepag, a hawk.) —A large 
and in Europe exceedingly difficult genus. The Mexican and Central 
American species erect perennial herbs with scapiform or leafy stems, 
alternate lance-linear to oblong or obovate, dentate or entire pinnately 
veined leaves and corymbose or paniculate heads; involucral bracts 
unequal, narrow, unaltered after anthesis, usually pubescent to bristly 
hirsute dorsally: corollas orange to lemon yellow, greenish white or 
rarely flesh-colored : achenes slender and cylindrical or attenuate from 
near the base toward the summit ; pappus copious, bright white to sordid, 
tawny, or rufous, of simple subequal bristles. — Inst. 469, t. 267 (1700) ; 
L. Syst. (1735), & Spec. 799 (1753) ; Fries, Symbol. Hierac. (1848), 
& Epicrisis Hierac. (1862); Sch. Bip. Ueber die Hieracien Amer- 
ika’s, Bonplandia, ix. 172 (1861); Benth. & Hook. f. Gen. Pl. ii. 516 
(1873); Hemsl. Biol. Cent.-Am. Bot. ii. 259 (1881); Arvet-Touvet, 
Spicilegium Hierac. (1881), Rev. des Epervitres & Elerchus, Ann. 
Conserv. Genév. i. 68 (1897); Gray, Proc. Am. Acad. xix. 65 (1884), 
& Syn. Fl. i. pt. 2, 424 (1884); Peter in Engl. & Prantl, Nat. 
Pflanzenf. iv. Ab. 5, 375 (1894); Hook. f. & Jacks. Ind. Kew. i. 1149 
(1893), which see for generic synonymy. 
* Pubescence of the leaves scanty to very copious, sometimes silky or hirsute, 
but not woolly or matted. 
+ Achenes fully 5 mm. in length, conspicuously tapering almost from the base to 
the summit. 
1. H. Fendleri, Scu. Bre. Stems 1 to 3, erect, 26 to 52 em. high, 
hirsute with long fine widely spreading or slightly reflexed bristles, or 
glabrate: basal leaves 3 to 14, oblanceolate to obovate, acute to- rounded 
and apiculate at the apex, cuspidate-serrulate, attenuate below, 5 to 12 
em. long, 17 to 60 mm. broad, covered on both surfaces and at the margin 
with long sparse hairs (bronze color in dried specimens) ; cauline leaves 
