4 R. H. Howe: MANUAL OF THE GENUS USNEA 
b] 
Type LocALity: ‘ Europae.’ 
ORIGINAL DESCRIPTION: ‘‘ Filamentosus ramosus erectus, scu- 
tellis radiatis,”’ L. Sp. Pl. 1156. 1753. 
Figures: [Micheli, Nov. Pl. Gen. p/. 39. fi se. 1739.]* 
[ Dill. Hist. Musc. p/. 73. f. 12, a,b,c, d; f. 13, a,6,c,d. 1741.] 
Willd. Rom. & Ust. Mag. Bot. 2: pf. 7. f. 3. 1788. Hoffm. 
Descript, et. Aduni: Pi..Lich; 2:-p/.. jan 72. 6-4 764, . ACK 
Kongl. Vet.-Acad. Nya Handl. 16: f/. 8. f. zr. 1795. Schrad. 
Jour. Bot. 1: f/. 3. f. 1, 2. 1799. Sowerby, Eng. Bot. 13: pi. 
872. 1801; 19: pl. 1354. 1804. Ach. Meth. Lich. p/. 6. f. 3. 
1803. Sprengel, Anleit. 3: p/. zo. f. ros. 1804. Fée, Essai 
sures Crypt $1.3.f. 4,6 5 pt. 32. f. 5. 1824, 
Synonymy: [ Usnea vulgatissima, ete. Dill. loc. cit. 67.| © 
Lichen floridus L. loc. cit. 1156. 
Usnea florida Web.; Wigg. Prim. Fl. Holsat. g1. 1780. 
Diacnosis: Thallus erect, cespitose. 
DescrIpTION —typical: Zhadl/us erect, cespitose, rigid, terete, 
virescent ; cortex soon scabrous, and annularly scarred ; primary 
branches coarse, divaricate (max. length 12 cm.); secondary branches 
subpedicellate, subdichotomous ; /dri/s short (6 mm.), sudeguiform, 
frequent or stipate, rectangularly divergent, rarely dichotomous. 
Apothecia common, terminal, ample, sometimes lacerate; disk 
pruinose, flesh-colored or buff, rarely virescent; periphery and 
thalline exciple ciliate. Spores 4-8 » x 3-6 yp. 
CONTINGENT PHASES: (@) With age blackening, crustose, brittle, 
leprous, abraded, nodular-bambusaceous, articulate, white medulla 
exposed, indurated cord visible. 
(6) Branches sorediate, soredia often becoming confluent near 
the apices (Lichen hirtus L. loc. cit. 1155). 
(c) Dichroic (red, either affecting all or part of the plant) (Usvea 
florida, var. rubiginea Michx. FI. Bor.-Am. 2: 332. 1803). 
(2) Strigose, apothecia very ample, disk now virescent (Usxea 
florida, y strigosa Ach. Meth. Lich. 2: 310. 1803). This phase ~ 
is most common in Mexican and Arizona plants. 
(e) Apothecia small, cyathiform. 
(7) Reduced, very cespitose, branches hispid and echinate. 
(g) Branches somewhat naked, furcate, and apices attenuate. 
(2) Nitidous or granulate, internodes somewhat inflated, apices 
* Pre-Linnaean references are enclosed in brackets. 
