320 LICHENACEI. [PHYSCIA. 



Tar. ft. virella Cromb. Grevillea, xv. p. 78. — Thallus subeffuse, 

 pale grej'ish-grecn, here and there greenish- or yelloAvish-sorediate ; 

 laciniae short, imbricate, with horizontal cilia at the margins. Apo- 

 thecia small or submodcrate, the receptacle black-fibrillose at the 

 base. — FJnjscia ohscitra var. virdJa Lcight. Lich. Fl. p. 148, ed. 3, 

 p. 137. Borrera ohsaira y. virdla Mudd, Man. p. 110. Parmdia 

 virella Sm. Eng. Fl. v. p. 202. Lichen virellus Ach. Prodr. (1798) 

 p. 108; Eng. Bet. t. 1696 (two upper figs.). Lkhenoides viride, 

 serpnentis angiistis distortis. scutellis jndlis Dill. Muse. 178, t. 24. 

 f/72 B.—Brit. Exs. : Mudd, n. 80 ; Larb. Lich. Hb. n. 126. 



Overlooking the character of the marginal cilia of the lacinise and of 

 the receptacle of the apothecia, licbeuologists have associated this distinct 

 variety with P. ohscura. As suggested by Xy lander in Hit., and coutirmed 

 by a specimen from Acharius in Herb. Linn. Soc. (fragmentary and 

 abraded, though suthcient for recognition), it entirely belongs to this 

 species. It ditiers from the type in the thallus being more eft'use, often 

 less closely appressed, paler in colour, and sprinkled with, or at times 

 almost covered by, roundish soredia, as also in the shoiter and usually 

 more imbricate lacinite. "When wet it is of a bright-green colour, and 

 when growing associated with P. parietina it is sufhised with chryso- 

 phanic acid, when the thallus and soredia are more or less yellowish (form 

 fiacescms Cromb."). It then gives a purplish reaction -with K, which, 

 however, is quite abnormal. To this state is referable Physcia etidococ- 

 cina (non Koerb.) Cromb. Jouni. Bot. 1872, p. 359; Leight. Lich. Fl. 

 ed. 3, p. 142. The cilia of the lacinise and the apotbtcia (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 blacki«h. 

 The apothecia and the spermogones are frequent in our specimens. 



Jlcih. On the trunks of old trees, rarely on walls, in iiiaritime and up- 

 land districts. — Distr. Not uncommon in most parts of England ; appa- 

 rently rare in N. Wales, Scotland, and S.E. Ireland. — B. M. : Kennetand 

 Ickwortb, Suffolk ; Epping Forest, Essex ; Heujield and near Brighton, 

 Su,ssex ; Ryde, Isle of "\Vight ; Ilsham, Torquay, Devonshire; ISewlyn 

 Clifi", Penzance, Cornwall ; neor Cirencester find Honey bourne, Glouces- 

 tershire : Gogmagog Hills, Cambridgeehire ; Darley, Derbyshire ; Aber- 

 dovey, Merionethshire ; Ayton, Cleveland, Yorkshire ; near Hexham, 

 Northumberland. Airds, Appin, Argyleshire ; Finlarig, Kilhn, and Glen 

 Fender, Blair Athole, Perthshiie. Killaloe, co. Cork; Lyons, near 

 Dublin. 



h. Spermogones with long aciuular 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 : lacinite 

 very narrow, multifid at the circumference, subleprose in the centre 



(K~, CaCl~). Apothecia small, plane, brownish-black, thethalline 



margin entire ; spores ellipsoid, 0,014-21 mm. long, 0,008-10 ram. 

 thick.— Cromb. Lich. Brit. p. 40 ; Leight. Lich. Fl. ed. 3, p. 137. — 

 Borrera ohscura e. cuhjlutinata Mudd, Man. p. 110 ; Leight. Lich. Fl. 

 p. 149. Lecanora adr/lvtinata Florke Deutsch. Lich. iv. ( 1 815) p. 7 ; 

 Tayl. in Mack. Fl. Hib. ii. p. 140. ParmeUa china Gray, Nat. Arr. 



