LKCAXOEA.J LECANO-LECIDEEI. 449 



leacens Cromb. Lich. Brit. p. 53 ; Leighfc. Lich. Fl. p. 231, ed. 3, 

 p. 223. Brit. E.vs. : Leight. n. 294 ; Mudd, n. 103. 



Closely allied to the preceding species, but among other characters, 

 apart from habitat, separated by the thecae being definitely 8-spored, the 

 spores themselves being normally straight. Mudd describes the thallus 

 of his plant, which is evidently only a state, as being leaden-greyish and 

 pruinose, both of which characters disappear in Herbaria specimen-*. 

 The apothecia are numarous and aggregate, with the margin, whan per- 

 sistent, at length undulate and angulose from their confluence. 



Hob. On old walls in upland situations. Distr. Very sparingly in W. 

 and N. England. B. M. : Preston, near Cirencester, Gloucestershire ; 

 near Marske, Cleveland, Yorkshire. 



Var. /3. caeruleorubella Cromb. Thallus thickish, granuloso- 

 leprose, sordid-greyish or ccesious. Apothecia innato-sessilo, scat- 

 tered, reddish or dark-red, the thalline margin whitish, persistent. 

 Lecania cceruleswns, var. ft. cceruleorubella Mndd Man. (1861) 

 p. 141. 



Probably a good variety, judging from the two specimens seen. It is 

 characterized by the more pulverulent thallus, the less prominent, more 

 scattered apothecia and their persistent thalline margin, otherwise it is 

 similar to the type. 



Hub. On old walls (arenaceous) in an upland district. Distr. 

 Extremely local and scarce in N. England. B. M. : Near Ayton, Cleve- 

 land, Yorkshire. 



142. L. dimsra Nyl. Not. Sallsk. pro F. et Fl. Fenn. Forh. xi. 

 (1871) p. 184. Thallus effuse, very thin, greyish-white, or scarcely 

 any visible (Kf-(- yellowish, CaCl ). Apothecia minute, biatorine, 

 convex, pale- or dark-brownish, naked, the margin thin, evanes- 

 cent; paraphyses not well discrete, brownish at the apices; epi- 

 thecium K + pale rose-coloured; spores 8nae, oblong or subellipsoid, 

 1-septate, usually somewhat curved, 0,012-18 mm. long, 0,004-6 

 mm. thick ; hymenial gelatine bluish, then wine-reddish or violet 

 with iodine. Cromb. Grevillea, xviii. p. 70. Lecanora athroocarpa 

 3. dimera Nyl. Lich. Scand. (1861) p. 169. 



Might readily be taken for L. syringea but for the number of the less 

 divided spores." In the single British specimen, which is well fertile, 

 the thallus forms small, somewhat scattered maculae on the substratum. 

 The young apothecia are distinctly lecanorine, but the thalline margin 

 speedily disappears. 



Hab. On the smooth bark of a poplar in an upland district. Distr. 

 As yet only very sparingly in the N. Grampians, Scotland. B. M. : 

 Mori-one, Braemar, Aberdeenshire. 



143. L. rhypariza Nyl. Ofvers. Vet.-Ak. Forh. 1860, p. 296 ; 

 Lich. Scand. p. 169. Thallus effuse, granulose or granuloso- 

 squamulose, pale, or pale-lurid-greyish, the granules (or squa- 



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