LECANORA,] I.KCANO-r.KCIDEEr. 435 



Var. /3. aitema Xyl. Flora, 1873, p. 22!).— Thallus somewhat 

 thickish, leprose, bright yellow. Apothecia small or subraoderato, 

 convex, lecideoid, black : spores 0,U12-17 mm. lonp:, 0,O(M.')-o5 

 mm. thick. — Cromb. Grevillea, xviii, p, 05). — Lecanora varia var. 

 aitema Cromb. Lich. Brit. p. 52; Leight. Lich. Fl. p. 102. L.si/m- 

 mk-ta var. aitema cd. 3, p. 183. Leci'ha aitema Ach. Lich. Univ. 

 (1810) p. 178. Lecanora varia i^.denirjrata (non Fr.), Mudd, Man. 

 p. 151. — Brit. Exs.: Cromb. n. 66; Larb. Lich. Hh. n. 2.35; 

 Mudd, n. lis. 



Looks entirely as if a Lecidea, near L. pnrasema. It is, however, 

 only a variety of this species, with which it agrees in the reactions, but 

 ditlers in the more leprose thallu* and the colour of the apothecia. The 

 thallus at times occurs in small determinate macula? and is alwavs well 

 fertile, the apothecia being colourless witiiin. A state in which there 

 are few or no traces of a thallus, with the apothecia crowded and often 

 less convex, is form depauperata Cromb. Grevillea /. c. 



Hah. On old palings in upland districts. — JDistr. Xot infrequent in Great 

 Britain ; not seen from Ireland or the Channel Islands.— B. M. : Xear 

 Lyndhurst, New Forest. Hampshire ; Shanklin. Isle of Wight ; Dart- 



shire ; Crathie, Braemar, Aberdeenshire ; Rothiemurchus, Inverness-shire. 



121. L. trabalis Xyl. Flora, 1877, p. 45^.— Thallus eflfuse, 

 glebuloso-granulate, subverrucoso-diffract, thinnish or siibmoderate, 

 greyish (K-|- yellowish, CaCl — ). Apothecia small, aduate, some- 

 what convex, immarginate, pale-livid, sordidly pale-testaceous or 

 livid-blackish ; spores rarely spuriously 1-septate, oblong, 0,009-- 

 0,014 mm. long, 0,0035-45 mm. thick ; ej^ithecium granulosa, 

 paraphyses slender : hymenial gelatine bluish, then subincolorous 

 (the thecfc subpersistently bluish) with iodine. — Lecidea scepincola 

 var. trabalis Ach. Syn. (1814) p. 35. 



Allied to L. symniictera, of which Xylander /. c. says it may perhaps 

 be a subspecies. In the British specimens, one of which was recently 

 determined by him, the thallus is chiefly dark-grey from age. The 

 apothecia are numerous and often difformi- connate. 



Hab. On a decorticated stump of hornbeam oak in a wooded upland 

 tract. — Distr. As yet only sparingly in E. England. — B. M. : Highbeech, 

 Epping Forest, Essex. 



122. L. piniperda Koerb. Par. Lich. (1865) p. 81.— Thallus 

 effuse, thin, verruculoso-leprose, whitish (Kf-1- ycUowish, CaCl — ). 

 Apothecia minute, plane or convex, subcarueous or brownish, 

 pruinose, the thalline margin pale, thin, entire, or subcrenulate, at 

 length excluded : spores oblongo-ellipsoid, 0,008-12 mm. long, 

 0,004-5 mm. thick ; hymenial gelatine deep blue, then tawny with 

 iodine. — Cromb. Journ. Bot. 1S73, p. 133; Leight. Lich. Fl. ed. 3, 

 p. 174. — Brit. Eas.: Leight. n. 176; Cromb. n. 160. 



2f2 



