386 LICHENACEL. [LECANORA. 
Often confounded with or regarded only as a variety of LZ. pyracea, to 
which it is externally similar, though definitely separated by the dis- 
tinctly-septate spores. It spreads extensively over the substratum, the 
thallus being frequently evanescent. ‘I'he apothecia are very numerous, 
and at times much crowded with a thalline margin rarely visible in their 
earlier stage of growth. Though normally a corticolous plant, it at 
times occurs on chalk, mortar, and limestone (very rarely in Britain), 
when it is form rupestris (? Scop.) Nyl. Lich. Scand. p. 145; Lecidea 
ulmicola Tayl. in Mack. Fl. Eib. ii. p. 129. 
Hab. On the trunks of trees, chiefly elms, rarely on rocks, from mari- 
time to upland situations.—Diustr. General in most parts of England, 
apparently rare in N. Wales, Scotland, and S. Ireland.—B. M.: Great 
Glenham and near Sotterly, Suffolk; Hale End, Epping Forest, Essex ; 
Eynsford, Kent; Lewes and Glynde, Sussex; near Ventnor, Isle of 
Wight; near Cirencester, Gloucestershire ; near Mill Hill, Middlesex ; 
Elstree, Herts; Windsor Great Park, Berkshire; Stowe Park, Bucking- 
ham; Wimpole Park, Cambridgeshire ; Twycross, Leicestershire; near 
Worcester and at North Malvern, Worcestershire ; Island of Anglesea ; 
near Masham, Yorkshire ; Leven’s Bridge, Westmoreland ; Meldon Park, 
Wansbeck Valley, Northumberland. Doune Castle, near Stirling ; 
Pitfour, Aberdeenshire. Castle Connell, co. Limerick; Rostellan, co. 
Cork; Inisfallen, Killarney,-co. Kerry. The saxicolous state has occurred 
only in the following localities in S. and N. England and §.W. Ireland :— 
South Downs, Sussex; Newton Abbot, 8. Devon; Ingleborough, York- 
shire. Dunkerron, co. Kerry. 
48. L. phlogina Nyl. Mém. Soc. Cherb. v. (1857) p. 112; Lich. 
Scand. p. 141.—Thallus effuse, very thin, minutely granuloso- 
leprose, citrine or yellowish-green ; granules globular, often some- 
what scattered (K+purplish). Apothecia small, biatorine, plane or 
at length convex, yellowish-orange ; spores elliptico-oblong, polari- 
bilocular, 0,011-15 mm. long, 0,006-9 mm. thick.—Cromb. Journ. 
Bot. 1871, p. 178; Leight. Lich. Fl. p. 223, ed. 3, p. 213.—Par- 
melia citrina var. phlogina Ach. Meth. (1803) p. 180.—Brit. Evs.: 
Larb. Lich. Hb. n. 57. 
Sometimes viewed as merely a corticolous state of L. citrina, but allied 
rather to L. pyracea, from which it is at once distinguished by the very 
different thallus. The apothecia are generally rather scattered. 
Hab. On the trunks of old trees, ash and elm, rarely on old posts from 
maritime to upland districts—Distr. Found only in a few localities in 
the Channel Islands and England.—B. M.: St. Clement’s Bay, Island of 
Jersey. Near Ryde, Isle of Wight; near Hastings, Sussex; Penzance, 
Cornwall; Windsor Great Park, Berks; Pampisford, Cambridgeshire ; 
near Worcester; Alston, Cumberland. 
Var. 6. lutea Nyl. Lich. Scand. (1861) p. 142.—Thallus leproso- 
pulverulent, whitish-citrine or pale-luteous. Apothecia pale-orange : 
spores 0,011-12 mm. long, 0,006-7 mm. thick.—Cromb. Grevillea, 
xviii. p. 46.—Lecidea epiwantha var. lutea Ach. Lich. Uniy. (1810) 
p. 209. 
A peculiar variety, differing in the more pulverulent, paler thallus, the 
san apothecia, smaller spores, and the nature of the habitat. The few 
ritish specimens are well fertile. 
