A’ar. p . v ir e lla Cromb. Grovillea, xv. p. 78.—Thallus subeffuse,
pale greyisli-grccn, here and there greenish- or ycllowish-sorodiate ;
laciniæ short, imbricate, with horizontal cilia a t th e margins. Apotheoia
small or suhmoderate, th e receptacle black-fibrillose " t t"®
Paso.— Physcia ohscura var. virella Leight. Lich. Fl. p. 148, od. 3,
p. 137. Borrera ohscura y. virella Aludd, Alan. p. 110. Parmelia
virella Sm. Eng. F l. v. p. 202. Lichen virellus Ach. Prodr. (1708)
1>. 108 ; Eug. Bot. t. 1690 (two upper figs.). Lichenoides viride,
seymeniis angustis distortis, scutellis gmllis Dill. AIuso. 178, t. 24.
f . 72 B .—B rit. Exs. : Aludd, n. 80 ; Larb. Lioh. Hb. n. 126.
Overlooking the character of the marginal cilia of the laciniæ and of
the receptacle of the apothecia, lichenologists have associated this distinct
variety with P. ohscura. As suggested hy Nylander in htt., and conhrmed
hy a specimen from Acharius in Ilerh. Linn. Soc. (fragmentary and
abraded, tliough suflicient for recognition), it entirely belongs to His
species. I t difiers from He type in the thallus being mpre effuse, often
less closely appressed, paler in colour, and sprinkled with, or a t tiines
almost covered by, roundish soredia, as also in the shorter and usually
more imbricate laciniæ. AA’lien wet it is of a bright-green colour, and
when »rowing associated with P. parietina it is suffused with chryso-
phanic acid, when the thallus and soredia are more or less yellowish (torm
fiavescens Cromb.). I t then gives a purplish reaction with K, which,
however, is quite abnormal. To His state is referable 2%se!« e«*eoc-
cina (noil Koerb.) Cromb. Journ. Bot. 1872, p. 350; Leigbt. Lich. 41.
ed 3 p 142. The cilia of He laciniæ and tbe apothecia (Irequently
abòeòt 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 H e spermogones are frequent in our specimens.
Ilah. On the trunks of old trees, rarely on walls, in maritime and upland
districts.—D;>ir. Not uncommon iu most parts of England ; apparently
rare in N. AA’ales, Scotland, and S.E, Ireland.—B. AI. ; Kennetand
Ickworth, Snffolk; Epping Forest, Essex; TIenlield and near Brigbtmi,
Sussex ; Ryde, Isle of AA'ight ; llsham, Torquay, Devonshire ; R ewlyn
Cliff, Penzance, Cornwall ; near Cirencester and Iloueyhouriie, Gloucestershire
; Gogmagog Hills, Cambridgeshire ; Darley, Derbyshire ; Aberdovey,
Alerionetlishire; Ayton, Cleveland, Yorkshire; near Ilexham,
Northumberland. Airds, Appin, Argylesliire ; Finlarig, Killm, and Gleu
Fender, Blair AHole, Perthsliiie. Killaloe, co. Cork; Lyons, near
Dublin.
h. Spermogones with long aoicular spermatia.
24. P. a d g lu tin a ta Nyl. Flora, 1862, p. 355.—Ih a llu s small,
orbicular, closely agglutinate, imbricato-stollato, sordid greenish-
grey ; beneath blackish, scarcely fibrillose a t the margins ; laciniæ
very narrow, multifid a t th e oiroumfereuoe, subleprose in th e centre
(K “ , C aC l/). ApotheoiasmaU, plane, brownish-black, th e th a llin o
margin entire ; spores ellipsoid, 0 ,0 1 4 -2 1 mm. long, 0 ,0 0 8 -1 0 mm.
thiok.—Cromb. Lich. Brit. p. 40 ; Leight. Lich. Fl. cd. 3,. p. 137.—
Borrera ohscura e. adglutinata Aludd, Alan. p. 110 ; Leight. Lich. Fl.
p. 149. Lecanora adglutinata Florke Deutsch. Lich. iv. (1815) p. 7 ;
Tayl. in Alack. Fl. Hib. ii. p. 146. Parmelia elceina Gray, Nat. Arr.
i. p. 439. Squamaria elceina Sm. Eng. Fl. v. p. 197. Lichen
eleeinus Eng. Bot. t. 21 6 8 .—B rit. Exs. : Cromb. ii. 152 ; Larb. Lich.
Hb. II. 49.
The tliallus is often leproso-pulverulent iu He centre, and sometimes
subiffuse, through He confluence of several plants. From states of P.
ohscura, of which it lias frequently been considered as a variety, it at
once differs in the form of the spermatia. The apotliecia are chiefiy
central. The spermogones, which are not uncommon, are olive-brown,
with spermatia long, acicuiar, about 0,018 mm. long, scarcely 0,001 mm.
thick.
Hab. On the trunks of trees, rarely on walls, in maritime aud lowland
d i s t r i c t s . P r o b a b l y not uncommon tbroughout Englaud and VA’.
Ireland ; rare in the Channel Islands ; apparently absent from Scotland.
—B. AI. : Noirmont, Island of Jersey. Norwich, Norfolk ; AA’althamstow,
Essex ; Glynde, llurslpierpoint, and between Henfield and Brighton,
Sussex ; Lymington, Hants ; Penzance, Cornwall ; near Cirencester,
Gloucestershire; Gamlingay, Cambridgeshire; Cleveland, A'orkshire;
Kendal, AA'estmoreland. Killarney, co. Kerry; Kylemore, co. Galway.
Eorm sorediata Nyl. ex Leight. Lioh. Fl. ed. 3 (1879) p. 138.—
Thallus leproso-sorediate almost throughout, glaucous-whito ; laciuiæ
more dilated a t th e oiroumi'erence and there only esorediate. Apothecia
uot seen.— Brit. Exs.-. Larb. Lioh. Hb. n. 127.
Apart from the paler colour and the bioader laciniæ this differs only
in the much more sorediate thaUus, in which respect it resembles var.
subvirella Nyl. (Pyr. Or. p. 63), w-liicli does not occur iu our Islands.
The specimens seen are sterile.
Hah. On walls and trees in upland districts.—Distr. Only sparingly iu
N.AA’. Ireland.—B, AI. : Letterfrack and Letter llill, Comiemar.a, co.
Galway.
Tribe X V II. G Y E O P H O E E I Nyl. Alera. Soo. Cherb.
iii. (1855) p. 175 ; Lich. Scaud. p. 112.
Thallus membranaceo-foliaoeous, monophyUous or subpolyphyUous,
peltate, umbilieately afflxed in the centre to the substratum, corticate
on both surfaces ; internaUy w ith white lax filamentose
medulla ; gonidial layer containing gonidia. Apothecia either lecanoroid,
or lecideine and gyrose, black ; spores solitary or usually
8næ, oblong or eUipsoid, simple or murali-divided, colourless or
brown ; paraphyses discrete. Spermogones e ith e r immersed or
somewhat prominent, with jointed sterigmata.
The systematic position of His tribe has been variously regarded by
authors. There is no doubt, however, that this is its true place as indicated
by the character of the vegetative and reproductive organs, though
the structure and form of He apothecia ai'e rather peculiar. I t is a very
natural tribe, comprising two genera, th e distinctive characters of which
have recently been definitely pointed out by Nylander. The species are
all saxicolous, characteristic of cold regions, and for He most part very
bi'ittle when dry.
Y
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