28 
NEW BRITISH LICHENS. 
0,008-0,014 m.m. long, 0,002-3 m.m. thick; paraphyses brown- 
clavate at the apices; epithecium and perithecimn brown; hyine- 
nial gelatine, at first bluish and then wine -reddish with iodine. 
On micaceous rocks. Connemara (Larbalestier). 
Nearest to L. ‘promimiUt, Borr., but with thinner thallus and 
different reaction with iodine. 
16. Lecidea tenebrans. Nyl. — Similar to L. contigna^ but with 
thallus leaden-greyish or dark leaden coloured (medulla I. partly 
bluish), and the hymenial gelatine with the thecae persistently 
intensely bluish. Spores 0,018-24 m.m. long, 0,010-13 m.m. 
thick. 
On micaceous schist. Connemara (Larbalestier). 
Probably a subspecies of L. contigua. 
17. Lecidea subumbonata. Nyl. — Thallus white, subopaque, thin, 
unequal ; apothecia black, opaque, plane, umbonate in the centre, 
margined, concolorous within, and often as if divided into several 
hymenia ; spores 8-nae, colourless, oblongo-ellipsoid, simple, 0,016- 
22 m.m. long, 0,007-9 m.m. thick; paraphyses not very distinct, 
epithecium and hypothecium brown ; hymenial gelatine bluish 
with iodine, and then the thecae tawny wine reddish; spermatia 
cylindrical (or obsoletely fusiformi- cylindrical), 0,004-7 m.m. 
long, 0,000 m.m. thick. 
On micaceous rocks. Connemara (Larbalestier). 
Belongs to the section of Lecidea juranuy Schaer. 
18. Xiecidea pedatula. JVyl . — Thallus whitish, granulose, thin 
(K yellow) ; apothecia black, minute, convex, immarginate, atten- 
uato-stipitate ; spores not seen rightly developed, thin section of 
hymenium bluish, epithecium rather dark, the stipitiform hypothe- 
cium reddish ; hymenial gelatine faintly bluish with iodine. 
On rocks, upon Sirosiphon snxicola. N.W. Ireland (Lar- 
balestier). 
Approaches in habit towards L. neglecta. 
19. Lecidea paxellaria. Nyl. — Allied to L. parasitica^ Flk., but 
with the spores 1-septate (much more rarely 3 septate), and the 
paraphyses blackish-clavate at the apices. Parasitic on the thallus 
of Lecanova parelia. 
Ireland (Larbalestier), formerly gathered in France (Nylander), 
and I believe I have seen the same in S.W. England. 
20. ArthoniaHibernica. Perhaps a subspecies of A. exci- 
pienda, from which it chiefly and constantly differs in the larger 
spores, which are 0,016-21 m.m. long, 0,006-8 m.m. thick. 
On smooth bark of trees. S.W. and N.W. Ireland (Carroll 
and Larbalestier). 
21. Graphis petrina. Nyl. — Thallus scarcely any visible ; apo- 
thecia black, linear, simple, subflexuose ; epithecium rimiform, 
narrow, and the margin tumid, on either side at least once 
sulcated, thence the lirella? are sulcated, the sulci being often 
