320 LICHENACEI. [pHYscIA. 
Var. 3. virella Cromb. Grevillea, xv. p. 78.—Thallus subeffuse, 
pale greyish-green, here and there greenish- or yellowish-sorediate ; 
laciniz short, imbricate, with horizontal cilia at the margins. Apo- 
thecia small or submoderate, the receptacle black-fibrillose at the 
base.—Physcia obscura var. virella Leight. Lich. Fl. p. 148, ed. 3, 
p. 137. Borrera obscura y. virella Mudd, Man. p. 110. Parmelia 
virella Sm. Eng. Fl. v. p. 202. Lichen virellus Ach. Prodr. (1798) 
p- 108; Eng. Bot. t. 1696 (two upper figs.). Lichenoides viride, 
segmentis angustis distortis, scutellis pullis Dill. Muse. 178, t. 24. 
f. 72 3.— Brit. Exs.: Mudd, n. 80; Larb. Lich. Hb. n. 126, 
Overlooking the character of the marginal cilia of the laciniz and of 
‘the receptacle of the apothecia, lichenologists have associated this distinct 
variety with P. obscwra. As suggested by Nylander ix Zétt., and confirmed 
by a specimen from Acharius in Herb. Linn. Soc. (fragmentary and 
abraded, though sufficient for recognition), it entirely belongs to this 
species. It differs from the type in the thallus being more effuse, often 
less closely appressed, paler in colour, and sprinkled with, or at times 
almost Covert by, roundish soredia, as also in the shorter and usually 
more imbricate lacinie. "When wet it is of a bright-green colour, and 
when growing associated with P. parietina it is suffused with chryso- 
phanic acid, when the thallus and soredia are more or less yellowish (form 
favescens Cromb.). It then gives a purplish reaction with K, which, 
however, is quite abnormal. To this state is referable Physcia endococ- 
cina (non Koerb.) Cromb. Journ. Bot. 1872, p. 359; Leight. Lich. Fl. 
ed. 3, p. 142. The cilia of the lacinie and the apothecia (frequently 
absent in the latter, as they occasionally are in the type itself) are at first 
pale, speedily becoming brownish, and at length in old plants blackish. 
The apothecia and the spermogones are frequent in our specimens. 
Hab. On the trunks of old trees, rarely on walls, in maritime and up- 
land districts.— Distr. Not uncommon in most parts of England; appa- 
rently rare in N. Wales, Scotland, and 8.E. Ireland.—B. M.; Kennet and 
Ickworth, Suffolk; Epping Forest, Essex ; Henfield and near Brighton, 
Sussex ; Ryde, Isle of Wight sham, Torquay, Devonshire; Newlyn 
Cliff, Penzance, Cornwall; near Cirencester and Honeyhourne, Glouces- 
tershire ; Gogmagog Hills, Cambridgeshire; Darley, Derbyshire ; Aber- 
dovey, Merionethshire; Ayton, Cleveland, Yorkshire; near Hexham, 
Northumberland. Airds, Appin, Argyleshire; Finlarig, Killin, and Glen 
Fender, Blair Athole, Perthshire. Killaloe, co. Cork; Lyons, near 
Dublin. 
b. Spermogones with long acicular spermatia. 
24. P. adglutinata Nyl. Flora, 1862, p. 355.—Thallus small, 
orbicular, closely agglutinate, imbricato-stellate, sordid greenish- 
grey ; beneath blackish, scarcely fibrillose at the ‘margins ; lacinie 
very narrow, multifid at the circumference, subleprose in the centre 
(K—,CaCl_). Apotheciasmall, plane, brownish-black, the thalline 
margin entire ; spores ellipsoid, 0,014-21 mm. long, 0,008-10 mm. 
thick.—Cromb. Lich. Brit. p. 40; Leight. Lich. Fl. ed. 3, p. 187.— 
Borrera obscura e. adglutinata Mudd, Man. p. 110; Leight. Lich. Fl. 
p. 149. Lecanora adglutinata Florke Deutsch. Lich. iv. (1815) p. 7 ; 
Tayl. in Mack. Fl. Hib. ii. p. 146. Parmelia elaina Gray, Nat. Arr. 
