112 
NEW BRITISH LICHENS. 
Communicated by the Rev. J. M. Crombie, F.L.S. 
r rhe following new species of Lichens recently discovered in Great 
Britain have been recorded by Dr. Nylanderin the “ Flora,” 1879, 
pp. 353-362, and 1880, pp. 10-13 : — 
1. Lecanora xantholyta. Nyl. — Thallus vitelline, entirely 
leprose, thin, sublobate, subeffigurate at the circumference (K + 
purplish) ; apothecia not seen. 
On limestone rocks ; always sterile. Great Orrne’s Head 
( Holmes) ; Bathampton Downs (Joshua) ; near Stokesay, Shrop- 
shire (Leighton). 
2. Lecanora superiuscula. Nyl. — Similar to Lecanora com- 
planata Krb. (Arn. Exs., n. 496), but differing chiefly in the 
spores being definitely larger, 0-010-14 mm. long, 0-007-8 mm. 
thick. Spermatia arcuate, 0-018-25 mm. long, 0-0006 mm. thick. 
On schistose rocks above Loch-na-Gat, Ben Lawers (Crombie, 
1878). 
3. Lecanora phaeleucodes. Nyl. Thallus whitish, effuse, areo- 
lato-dififract ; apothecia small, brown, biatoroid, immarginate ; 
hymeneal gelatine bluish and then wine -reddish (especially the 
thecas) with iodine. Spermatia arcuate, 0*016-20 mm. long, 
0-0005 mm. thick. 
On calcareous rocks, Island of Lismore, Argyleshire (Crombie, 
1877). 
Nylander observes that this is almost a variety of L. erysibe , but 
it has the external appearance of L. leucophcea, and approaches to 
L. subalbens Nyl. 
4. Lecidea illita. Nyl. — Thallus subisabelline or pale-greyish, 
thin or very thin, appl anate, areolato-diffract, areolas angulose 
(Ca. Cl. + red); hypothallns very thin, umbrine- black ; apothecia 
black, innate, 1 or 2 in each thalline squamule, minute, margined, 
umbonate in the centre ; spores 8 nas, ellipsoid, simple, 0-012-16 
mm. long, 0-008-0-011 mm. thick, paraphyses slender, somewhat 
sparing, perithecium and umbo in thin section brownish- black ; 
hypothecium thin, subcolourless ; hymeneal gelatine tawny wine- 
red with iodine ; spermatia acicular, 0-005-6 mm. long, 0*0005 mm. 
thick. 
On argillaceous schist in the W. of England (Larbalestier). It 
is closely allied to L. umbonatula Nyl. 
5. Lecidea tabidula. Nyl — Thallus blackish, thin or very thin, 
unequal, subscattered ; apothecia black, minute, plane, somewhat 
margined, often aggregated, concolorous within ; spores 8 nae, 
ellipsoid, 0*011-16 mm. long, 0*006-7 mm. thick, epithecium sordid 
bluish-black, paraphyses not well discrete, hypothecium (with the 
perithecium) dark-brown (or reddish-brown in thin section) ; 
