83. ARTHONIA Ach. in Schrad. Neu. Journ. Bot. i. 3,
p. 3 (1806) emend. & Lich. Univ. p. 25 (1810). (PI. 20.)
Thallus crustaceous, thin or evanescent, sometimes developed
under the bark (hypophloeodal). Algal cells Trentepohlia or
Palmcllaccæ. Apothecia innate, sessile, immarginate, roundish
{ardellæ) or elongate (lirellæ), plane or tumid ; asci pyriform
or almost globose, rarely elliptical, thickened a t the apices ;
spores elongate-ovate or clavate, 1- or pluri-septate, colourless
or sometimes brownish.
Includes a number of species th a t have been formerly classified
under different genera, according to the form of the thallus or spores ;
they are grouped in three sections ;—
Thallus with Trentepohlia gonidia.
Apothecia more or less brightly
coloured or b row n ............................ § i. C o n i o o a r p o n ( 1 - 6 ) .
Apothecia blackish ............................... § ii. E u a r t h o n i a (7-20).
Thallus with Palmella gonidia, or
w a n tin g § ifi. L e c i d e o p s i s (21-28).
§ i. CONIOCAEPON A. Zahlbr. in Engler & P ran tl Nat.
Pflanzenf. i. 1*, p. 91 (1903).— Coniocarpon DC. PL P r. ii.
p. 323 (1805), pro p a rte ; Leight. in Ann. Mag. Nat. Hist,
ser. 2, xiii. p. 433 (1854).
Algal cells Trentepohlia. Apothecia brightly coloured or
brown, not black ; spores 1- or more-septate.
Spores 1-septate.
1. A. lurida Ach. Lich. Univ. p. 143 (1810).—Thallus thin,
pale-dirty-brown or pale-lead-coloured, smooth, effuse or obsolete.
Apothecia {ardellæ) reddish or reddish-black, sessile, appressed,
irregularly roundish, slightly convex (K + v io le t or blue) ; spores
broadly ovate, 1-septate, colourless or pale-yellow, 0,010-15 mm.
long, 0,004-6 mm. thick ; hymenial gelatine dirty-wine-red with
iodine.—Borr. Engl. Bot. Suppl. t. 2692, fig. 2 ; Hook, in Sm.
Engl. El. V. p. 143 ; Tayl. in Mackay El. Hib. ii. p. 104 ; Leight.
in Ann. Mag. Nat. Hist. ser. 2, xiii. p. 442, t. 8, fig. 38 (1854)
&_Lich. FL p. 391 ; ed. 3, p. 414 ; Mudd Man. p. 250 ; Oromb.
Lich. Brit. p. 102 (excl. f. vinosa).
Exsicc. Mudd n. 236 ; Leight. n. 224 (as A. vinosa).
Hab. Usually on the trunks of small tmes.—Distr. Frequent in
England, somewhat rare in the Channel Islands, W. Scotland and in
S. Ireland.—B. M. Withiel, Cornwall ; Baloombe, Blackdown, Hand-
cross and Hurstpierpoint, Sussex; near Becky Falls and Newton
Bushel, Devon; New Forest, Hampshire; Gopsall, Leicestershire;
Bettws-y-ooed and Trefriw, Carnarvonshire ; Sutton, near Shrewsbury,
Shropshire; Malvern, Worcestershire; Airyholme Wood, Cleveland,
Yorkshire ; Windermere, Westmoreland ; Mangerton and Dunkerron’
Kerry. ’
S^dicea Nyl. in Mem. Soc. Sci. Nat, Cherb. iv. p. 92
(1 bob).—Differs from the species in the somewhat darker
apothecia and in the shorter unequally divided spores, 0,011-
Ifi mm. long, 0,004-5 mm. thick, the lower cell being frequently
elongate, bi-guttulate and spuriously divided.—Mudd Man.
p. -.51. Subsp. spadicea Cromb. Lich. Brit. p. 103 (1870)
Arthonia spadicea Leight. in Ann. Mag. Nat. Hist, ser 2 xiii
p. 442, t. 8, fig. 39 (1854) & Lich. El. p. 393; ed. 3, p. 417’.
Exsicc. Leight. n. 97.
F n S irunks of trees -DZsZr. Rare in the Channel Islands,
K XT I f4 a n d .-A . M. Jersey; Lustleigh, Devon; Lynd’
hurst. New I orest, Hants; Midhurst, Sussex; Chedworth Woods
Gloucestershire; by the Wye, near Monmouth ; Gopsall, Leicesterä
'l?5®” one Carnarvon-
F Dojlg^i, near Shrewsbury, Shropshire; Ayton, York-
N e st’KUWrK^^^^^^^^ " Enniskean, Cork ; Muckruss and Eagle’s
2. A. didyma Koerb. in Schles. Ges. Denkschr. Breslau 1853
p. 23o, emend. ; Almqu. in K. Svensk. Vet.-Akad. Handl. xvii.’
n 6 p. 13 (1880).—Thallus thin, effuse, smooth or furfuraceous,
whitish, or pale-brown. Apothecia small, crowded irregularly
roundish, deep vmous-red or blackish, vinous-red within (K +
violet or blue) ; spores obovate, colourless becoming brownish
1-septate, 0,015-18 mm. long, 0,006-8 mm. th ick ; hymenial
gelatine greenish then blue with iodine.—A. pineti Koerb. Syst
Lich Germ p. 292 (1855); Cromb. Lich. Brit. p. 104. A. vinosa
o ii ' 4- ser- 2, xviii, p. 331 (1856) &
Lich. EL P- 391i ed 3, p. 414 (incl. yav. pineti Leight.); Mudd
Man. p. 250. A. lurida f. vinosa Cromb. Lich. Brit p 103
(1870) A. sapineti Nyl. in Plora lix. p. 239 (1876) ; Cromb in
Grevillea v. p. 30 ; Leight. Lich. FL ed. 3, p. 415.
Exsicc. Mudd n. 235.
Intimately related to A. lurida, but differing in the paler thallus,
the somewhat larger spores, and in the reaction of the hymenial
gelatine with lodme. Leighton’s specimen (n. 224), as noted by
Almqu. {I. c.), belongs to the preceding species.
,, *41® bark of trees.—Disir. Somewhat rare throughout
tee Biitash Isles.—A. M. Lustleigh, Devon; New Forest, H an ts;
Danbury, Essex; Brandon Forest, Wilts; Ulohin Wood, Norton,
Woroesteiy Builth, Brecknockshire; Dolgelly, Merioneth; Church
s l f d T ’ 8troP®4iire; Gwydir Woods, Bettws-y-Coed, Carnarvonshire;
Stagdale, Cleveland, Yorkshire ; Barcaldine, Argyll; Aberfeldy, Perthshire
; Castle Bernard and Enniskean, Cork; Killery Bay, Conne-
mara, Galway. ^
3. A. atrofuscella Nyl. in Flora Iviii. p. 363 (1875).—Thallus
whitish-glaucous, smooth. Apothecia minute, punctiform, reddish-
black ; spores obovate, 1-septate, colourless, becoming brownish,