[ 2455 ]
L I C H E N viridulus.
Greenish Dot Lichen.
CRYPTOGAMIA Alga;.
G e n . C h a r . Male, scattered warts.
Female, smooth shields or tubercles, in which the
seeds are imbedded.
Spec. C h a r . Crust imperfectly circumscribed, very
thin, cracked, pale greenish olive. Tubercles
black, hemispherical, pointed, prominent through
irregular openings.
Syn. Lichen placothallus. Ach. Prod. 18.
Endocarpon viridulum. Schrad. Spirit. 192. t. 2.f 4.
Verrucaria viridula, Ach. Meth. suppl. l6.
C'OLLECTED by Miss Hutchins, on fissile slate rocks, in
shady situations, in the west of Ireland, and communicated to
us by Mr. W. Borrer.
The very thin and inseparable crust forms broad washy stains,
very loosely circumscribed, of a greenish olive when wet; more
grey and shining when dry. Plentiful tubercles are scattered
throughout the crust, each bursting at first through an irregular
star-like crack ; but they soon rise above the surface, appearing
partly denudated, and on dissection are found to be black, hemispherical,
with a central papillary elevation. At length a small
circular depression is perceptible in the summit of this protuberance.
L. viridulus, Ach. Prod. 29, is a Variolaria, which genus we
have already adopted; see v. 34. 2400.