BRITISH LICHENS

330 PYRENOCARPElE POL YBLASTIA
Hab. On rocks, mostly culcureous.-Dislr. Rure in W. England,
N. Scotland und W. Irelund.-B. M. Craig Tulloch, Blair Athole,
Perthshire.
,
Spores colourless becoming brownish.
5. P. Schraderi A. L. Sm.-Thallus greyish-white, thin,
tartareous and somewhat farinose. Perithecia black, globose,
deeply immersed and leaving pits in the rock, the ostiole only
slightly emerging; perithecial wall entire; spores 8 in the ascus
ellipsoid, muriform, usually 3-septate with an irregular longitudinal
division, colourless, becoming brownish, about 40-45 (1.
long, 12-17 (1. thick.-Lichen Schraderi Sm. Eng!. Bot. t. 1711
(1807) (non Ach.). Lithocia Schraderi S. F. Gray Nat. Arr. i.
497 (1821). Verrucaria Schraderi Winch Bot. Guide Northumberland
and Durham, 44 (1805).
Exsicc. Bohl. n. 9, pI.? (as Verrucaria rupestris).
The perithecia are thickly scattered over the stone and tend to
grow in concentric lines, u churacter distinctive of Bohler's plate. There
are also present on the surface of the stone small groups of Verrucaria
Dufourii, probably the" male scattered warts" of Smlth's description.
Hab. On chalk or calcareous stones.-Distr. Rather rare in limestone
districts.-B. IJf. Sussex (specimen collected by W. Borrer); Crickley
Hill, near Chcltenham, Gloucestershire; Dovedale, Derbyshire; near
Aviemore, Inverness·shire; Lough Gill, Sligo.
6. P. deminuta Am. in Flora xliv. 264 (1861).-Thallus
greyish-white, thin, tartareous. Perithecia globose, minute, black,
entirely immersed, leaving pits in the rock, the ostiole slightly
prominent; perithecial wall entire; asci ventricose (ca. 70-85 (1. by
45 (1.); paraphyses none; spores 8, colourless then brown, ellipsoid
or broadly oblong, muriform, and with a mucilaginous epispore,
22-30 (1. long, 9-16 mm. thick.-Verruca ria deminuta Cromb. in
Joum. Bot. xiv. 363 (1876); Leight. Lich. FI. ed. 3, 491 (errore
diminuta).
This and the preceding are the only British species of Polyblastia
that form perithecial pits (foveolate) in the substratum.
Hab. On moist rpcks.-B. M. Near Cheltenham, Gloucestershire;
Moryliton Fell, Yorkshire; Recess Road, Connemara, Galway; Lough
Gill, Sligo ( ?).
7. P. inumbrata A. L. Sm.-Thallus dark-brownish or greyish,
thin, effuse, unequal or dispersed. Perithecia moderate in size,
semi-immersed, the ostiole projecting, generally with a m nut('
papilla; perithecial wall thick, black, entire; paraphyses mucilaginous,
disappearing; spores 8 in the ascus, oblong-ellipsoid.
light-yellowish-brown, muriform, large, 33-62 (1. long, 17-32 (1.
thick; hymenial gelatine wine-red with iodine.-Verrucaria
inumbrata Ny!. in Flora xlvii. 355 (1864); Carroll in Joum. Bot.
iii. 292 (1865); Cromb. Lich. Bnt. 114; LLight. Lich. FI. 460;
ed. 3, 492.