Pi. cell. aph. 3. HOMOTHALAMEZE. 87. Usnea. 403 
B. Usneapem. Thallus slightly crustlike, penetrated 
by an elastic, central bundle of ducts; apothecia regular, 
shieldlike, pedicelled, sometimes proliferous from the edge ; 
pedicels central, accompanied with cephalodia and sorediez. 
VIII. 87. USNEA. Dillenius. 9 © ¢ Usnea. 
Thallus slightly crustlike, rather cylindrical, branched, 
mostly hanging down, enclosing a transparent, central, 
elastic, threadlike bundle of ducts; apothecia orbiculate, 
terminal, shieldlike, eatirely formed of the thallus, and 
covered in every part with its cortical substance, keeping 
nearly the same colour, circumference without any defined 
edge, generally fringed. 
1. Usnea florida. Florid usnea. 
‘Thallus rather upright, rough, pale grey; holdfasts slen- 
der, horizontal; lranches very much spread, scarcely 
branched ; apothecta flat, very broad, whitish, fringed ; 
fringe radiating, long. 
Lichenoides quod Muscus arboreus cum orbiculis, Raii Syn. 65, 4. 
Lichen floridus, Lin. §. P. 1624; Eng!, Bot. 872. 
Usnea florida, Achar, Meth. Lich. 307 ; Lick. Un. 620. 
On trunks of old trees and palings. 
B. rigida. Thallus long, stiff, straight, very siender, 
rather hanging, rough; branches rather long, bent, 
branched, twiggy. 
y. rubiginea. Thallus rather hairy, rusty red; cpothecia 
of the same colour. 
2. Usnea plicata. Folded usnea. 
Thallus hanging, smooth, pale; branches weak, very 
much divided, the last twigs hairlike; apothecta flat, broad, 
fringed; fringe very fine, very long. 
Lichenoides quod Muscus arboreus, Usnea officinarum, Raii Syn. 64,1. 
Lichen plicatus, Lin, S. P. 1622; Engl. Bot. 257. 
Usnea plicata, Achar. Lich. Univ. 622. 
Hairy tree-moss. 
From the trunks and branches of trees. 
6. comosa. Thallus slightly upright, shrublike, pale 
white; side branches very much spread, diffuse, smooth, 
much divided; last twigs fibrelike, rather rough, slightly 
nodding; cephalodia pale flesh-colour, growing brown. 
Lichen comosus, Achar. N. Act. Stockh. 16,209. 
Usnea plicata comosa, Achar. Meth. Lich, 31i; Lich. Univ, 623, 
Zp 2 : 
