been found in other parts of France, in Switzerland, and in
Germany.
Crust spreading in wide patches, with a tendency to a circular
outline, and usually bounded by a narrow black or
brownish line : substance thicker than in V. epipolaa, white
within, except a very thin green layer immediately under
the surface : surface of a somewhat pruinose appearance,
grey, tinged more or less deeply with mouse-colour, level,
continuous at first, at length divided by minute cracks,
perceptible under a glass and in a dry state only, into small
areolae. Tubercles numerous, regularly scattered, about
the size of cabbage-seed, hemispherical or even more prominent;
the base sometimes slightly dilated, sometimes contracted,
slightly immersed in the thallus; the apex usually
truncate, or, when dry, concave, the large circular dimple
surrounded by a narrow edge, and sometimes furnished with
a central papilla; shell black, occasionally polished, but
usually not without a slightly pruinose appearance when
dry, incurved at the base, but not subtending the whole of
the nucleus, which is pale, brownish in a dry state, and
then more or less shrunken, yet still sometimes almost filling
the shell. Not unfrequently two or more tubercles
form by their confluence a compound apothecium : except
when this takes place the shape of the tubercle is usually
regular.—W. B.
Fig. 1. represents the appearance of the plant when dry,
and fig. 2. when moistened.