3796
PA R M E LI A ambigua.
Ambiguous Parmelia.
CRYPTOGAMIA Lickenes.
Gen. Chau. Scutellce formed from the thallus, affixed
by a central point, the circumference free. Disk
of a different substance from the margin.
Spec. Char. Thallus very thin, appressed, stellated,
bearing flattish powdery warts; segments flat, linear,
dichotomously many-cleft; undersidebrown,
fibrillose. Scutellse small, flattish ; disk browm ;
margin slightly elevated, powdery.
a. greenish yellow.
S y n . Parmelia ambigua. Ach. Meth. 307. Lick.
Univ. 485. Syn. 209. Hook. FI. Scot. P. 3. 55.
Brit. FI. v. 3.303. Fries, Lich. Eur. Reform. 71.
Duby, Bot. Galt. 603.
P. diffusa(3. BluffetFing. FI. Germ. Comp. v .3.497.
Squamaria ambigua. Hoffm. PI. Lich. 56. t. 40.
ƒ. 3—4. t. 42. f . 3, 3.
Lichen ambiguus. Wulf. in Jacq. Coll. v. 4. 339.
t. 4. f . 3. Ach. Prod. 117. Wahl. FI. Lapp.
439. FI. Suec. 818.
f3. white.
Parmelia ambigua (3. Wahl. FI. Suec. 1. c.
P. diffusa a. Bluff et Fing. 1. c.
Lichen diffusus. Web. Spicil. Goett. 350.
NATIVE of Scotland and Wales, chiefly on old fir-
trees, very rarely producing its apothecia. Our barren
specimens were gathered in 1808, the yellow variety in the
ascent of Larig Crue under Cairn Gorin? the white in the
neighbouring Forest of Rothiemurehus ; that with shields
at a, was sent by the late Mr. G. Don from Marr Forest,