j r [ 2519 ]
CRYPTOGAMIA Algae.
Gen. Char. Receptacles cup-shaped, with a torn
border from the crust, powdery, with a fertile
disk beneath.
Spec. Char. Crust tartareous, thickish, greyish
white, cracked, tumid, papillary and ru g g e d ;
obscurely zoned at th e circumference. Receptacles
orbicular, prominent, white, with an aggregate
internal disk.
Syn. Variolaria dealbata. Decand. Franc, v. 2. 525 ?
V. corallina. Ach.Lich. Univ. 319 . t. 5. f . 6.
Lichen dealbatus. Ach. Prodr. 29.
Isidium corallinum, a supposed variety. Ach. Meth.
138. t. 3. ƒ. 7 ; bad.
I . paradoxum. Turn. & Borr. Lick. Brit. v. 1 . 9 7 .
W e are obliged to Mr. Turner for this very complete specimen
; but we have received others from various British friends,
as well as from Dr. Acharius. The plant is not rare on hard
rocks, in mountainous countries.
It differs from V. laclea, t. 2410, in having a very narrow,
imperfectly zoned, border, but especially in the crust bearing
scattered, cylindrical, papillary processes, often two together.
The receptacles, when young, are small, concave, powdery,
white cups; but when arrived at maturity, which happens to a
few of them only, they become raised and convex, as large as
hemp-seed, their surface still white and powdeiy, but finally displaying
several little, concave, brownish or flesh-coloured, separate
disks.
The learned authors of the Lichenographia Britannica, from
whom we have taken our two first synonyms, consider this plant
as an Isidium, on account of the papillae, not without a most
candid expression of their doubts.. We dissent from them with
much hesitation ; but having, in no species, been perfectly satisfied
of the nature of those papillae, we are now led the more to
doubt their being the fruit, and we rather rely on the receptacles,
obviously agreeing with Variolaria.