Well characterized by the form, septation and size of the spores,
which readily distinguish it from all the allied species. The apothecia,
somewhat scattered, are semitransparent, and become in age less
concave, with the margin darker. At times the whole plant is more
or less infested by Lepraria rubens Ach.
A plant corresponding with this in the form and septation of the
spores is L. cJirysophcea Nyl. in Act. Soc. Linn. Bord. ser. 3, t. i.
p. 438 (1856); but this is doubtfully British. Lecidea pallida Nyl.
I. 0., with ohlongo-fusiform 3-septate spores, is more probably a
fungus {of. Nyl. Lioh. Scand. p. 192).
Hah. On smooth bark of trees in wooded maritime and upland
districts.—Distr. Somewhat rare in England and Wales ; rare in S.W.
Ire la n d ; not seen from Scotland or the Channel Islands.—B. M.
Near Eyde, Isle of W ig h t; Lyndhurst, New Forest, H a n ts ; Lnstleigh,
Devon; Ashdown Forest, Tilgate, and Bridge Park, Sussex; Twycross,
Leicestershire; Barmouth, Merioneth; Trefriw, Garn and Gwdir,
Denbighshire; Haughmond Hill, Shropshire ; Eglestone and Teesdale,
Du rh am ; Keswick, Cumberland ; Dinis, Killarney, Kerry.
71. LECIDEA Ach. Meth. p. 32 (1803); Nyl. emend, in
Mém. Soc. Cherb. t. iii. p. 181 (1856).
Thallus squamose, pulverulent, granulóse, continuous, areolate,
rimulose, evanescent or a b s e n t; hypotballus various, persistent
or indistinct. Algal cells Protococcus or rarely Trentepohlia.
Apothecia either discolorous (not black) and biatorine, or black
and lecideine, the proper margin often obliterated; spores usually
eight in the ascus, ellipsoid or oblong, simple, colourless ; hymenial
gelatine variously tinged with iodine. Spermogones with spermatia
acicular, straight, rarely arcuate, or shortly cylindrical.
This extensive genus has been grouped under four sections. The
spores are colourless and simple or rarely faintly 1-septate ; the asci
are 8- or sometimes 6-spored, excepting in the section Megalospora
which contains one species with a 1- or 2-spored ascus. The term
biatorine, from Biatora, has been applied to those apothecia th a t are
lighter in colour and soft in texture, while lecideine signifies the
dark almost black fruits th a t are carbonaceous and hard, and th a t
belong more particularly to the Eulecidece. There is, however, no
clear line of demarcation, as the colour and form of the fruits change
with age. The genus is very well represented in our islands, where a
considerable number of species seem to be endemic. The ohemioal
reactions, which have been given as far as possible, will be found to
be useful in distinguishing plants which otherwise might readily be
confounded. The species within the genera have been grouped as
nearly as possible in the order followed by Nylander and subsequently
by Hue and Crombie.
Thallus distinctly squamulose................ § i. P s o b a (1-15).
Thallus variously crustaceous.
Ascus 8-spored.
Apothecia lighter in colour ........... § ii. B i a t o e a (16-76).
Apothecia dark and carbonaceous § iii. E i j l e c i d e a (77-200).
Ascus 1- or 2-spored.
Apothecia dark ................................ § iv. M y o o b l a s t u s (201-2).
§ i. P sora Haller Hist. Stirp. Helv. iii. p. 93 (1768) e t auctt.,
pro parte. (PI. 5.)
Thallus squamulose; spores 8nate. Spermogones with simple
sterigmata and straight spermatia.
1. L. lurida Ach. Meth. p. 77 (1803) & Syn. p. 51 (1814).—
Thallus imbricato-squamose, appressed, caispitose, lurid or lurid-
brown, opaque (K—, CaCl—) ; squamules orbicular, rigid,
smooth, sinuate-lobed. Apothecia moderate, adnate, plane,
brownish-black, pale within, the margin obtuse, slightly flexuose,
a t length convex and immarginate; hypothecium thick, dark-
brown ; paraphyses stout, coherent, reddish-brown a t the
apices; spores ellipsoid or oblong-ellipsoid, 0,013-15 mm. long,
0,005-7 mm. th ic k ; hymenial gelatine slightly bluish then
wine-red with iodine.—Hook. FI. Scot. ii. p. 40 ; Carroll in Nat.
Hist. Rev. vi. p. 525; Cromb. Lich. Brit. p. 64 ; Leight. Lich.
FI. p. 252 ; ed. 3, p. 244. Lichen luridus Sw. in Nov. Act. Hpsal.
iv. p. 247 (1784); Dicks. Crypt, fasc. ii. p. 20 ; With. Arr. ed. 3,
iv. p. 28 ; Engl. Bot. t. 1329. Lepidoma luridum S. E. Cray
Nat. Arr. i. p. 460 (1821). Psora lurida DC. El. Er. ii. p. 370
(1805); Mudd Man. p. 170. Lichenoides pulmonarius saxatilis
viridis, etc., Dill. Hist. Muse. p. 228, t. 30. f. 134 (1740).
Exsicc. Dicks. Hort. Sicc. n. 25 ; Cromb. n. 79 ; Larb. Ceesar.
n. 31, Lich. Hb. n. 340.
When sterile and only spermogoniiferous might readily be taken for
an Endocarpon allied to E. liepaticum Ach. In more shady situations
the thallus is occasionally pale-brown, with the squamules more
concrete, when it is form pallescens Th. Fr. Lioh. Scand. p. 414
(1874), a condition which rarely occurs in this country. The apothecia
are generally rather scattered and in age become black.
Hab. On calcareous soil among rooks in maritime and upland
districts.—Distr. Here and there in Great Britain and the Channel
Islands, though plentiful where it occurs; not seen from Ireland.—
B. M. St. Ouen’s Bay and Portelet Bay, J e rs e y ; Saints’ Bay,
Guernsey; above Anstey’s Cove, Torquay, Devon; Yatton, Herefordshire
; Cheddar Cliffs and Bathford Hill, Somerset; Cunning
Dale, near Buxton, and above Cromford, Derbyshire; Dolgelly,
Merioneth; Great Orme’s Head, Carnarvonshire; Teesdale and
Eglestone, Du rh am ; Cumberland; King’s Park, Edinburgh ; Island
of Lismore, Argyll; Ben Lawers, Perthshire; Clova Mts., F o rfa r;
Craig Guie, Braemar, Aberdeenshire.
2. L. globifera Ach. Lich. Hniv. p. 213 (1810).—Thallus
squamoso-imbricate, somewhat shining, areolate, reddish-brown
or chestnut-red, paler beneath (K —, CaCl — ) ; squamules reni-
form, rigid, roundly lobed, flexuose, subhorizontal. Apothecia
small, prominent, convex, a t length globose, immarginate, often
conglomerate, brown or brownish-black, pale w ith in ; paraphyses
coherent, reddish-brown a t the apices; hypothecium thin,
brownish; spores subellipsoid, 0,012-15 mm. long, 0,005-6 mm.
th ic k ; hymenial gelatine slightly bluish then wine-red with