opening. Little black specks are found here and there on
the crust, which seem to be the bases of broken tubercles.
The powdery surface of its tubercles seems to indicate
some degree of affinity between this most inconspicuous
little Lichen and V. leucocephala; and the state of our
knowledge of these obscure vegetables is by no means such
as to warrant a positive assertion that it is not an infant
state of that species, only in company with which we have
hitherto found it growing. Yet the structure of the crust
seems very different, as well as the colour both of that part
and of the fructification. The tubercles are much more
minute than those of any other Verrucaria with which we
are acquainted, being of scarcely half the size of those of
the American species which Acharius has named V. pusilla,
in which they are, indeed, about as large as in V. rhypontai
t. 2597. f . 2. We are not acquainted with V.byssacea\ar.
minutissima of Acharius, (Syn. Lich. p. 97.) but it can bear
no near resemblance to our V. aphanes.—W.B.
2642. (Pig. 2.)
V E R R U C A R I A leucocephala.
White-fruited Verrucaria.
CR YP TO GAM I A Hellenes.
Gen. Char. Tubercles of a different substance from
the thallus, simple, convex, not expanding, but
furnished with a central pore, and inclosing a
somewhat gelatinous nucleus.
Spec. Char. Crust between filmy and tartareous,
grey, pruinose. Tubercles largish, prominent,
spherical or almost cylindrical, brown, covered
with white powder; their apex at length bare.
Syn. Verrucaria leucocephala. Ach. Meth. 116. Lich.
Univ. 286.
Pyrenula leucocephala. Ach. Syn. 126.
Cyphelium leucocephalum. Ach. in Stockh. Trans,
fo r 1817, 226. “ t. 8 .f .7 .”
Sphseria lichenoides. Sowerby Fungi, t. 373. f . 12.
|8. amphibola. Ach. Syn. I. c.
Lichen amphibolus. Ach. Prod. 20.
T h i s species, which is, according to Acharius, the
Sphceria leucocephala of Ehrhart and of Persoon, grows
near the ground, on the trunks of old trees. The presence
of the genuine thallus of a Lichen claims for it a place in
this Order; and its tubercles are similar to those of the
other Verrucarice in internal structure, although they recede
much in outward appearance, by their soft funguslike
look and powdery surface.
The crust spreads widely and irregularly. Young patches
are usually roundish, and have sometimes a fibrous and