358 



J. A. MARTINDALE : NOTES ON BRITISH LICHENS. 



4. Lecanora lobulata Smrft., Lapp., p. 87, a.d. 1826; Nyl., Flora, 



1 88 3, p. 105. Flacodium vnirorinn v. lobiilatiim Leight., 

 Lich. Flora, p. 161, and P. ininiatum v. obliferafum Ibid., 

 p. 162. 



Exs. — Hepp., 71; Anz., Langob., 275a; Leight., 207; 

 Mudd., 95 ; Larb., Lich. Herb., 295. 



Thalhis areolate or subsquamuloso-lobulate, not radiating, 

 areolae scattered or contiguous, effuse, imposed upon a pale 

 hypothallus, which often forms a thin subfibrous margin 

 round the plant, vitelline or intensely miniate. 



Apothecia with disc generally deeper in colour than the thallus, 

 and having a paler entire border, sometimes becoming 

 obsolete. Paraphyses stout, articulate, slightly branched, 

 upper cells much swollen, apical cells subspherical, up to 

 •007 mm. diam. Spores ellipsoid, -010- '014, mm. long and 

 ■005- '006 mm. broad. 



Spe7'mogo7iia comparatively large, easily found in the vitelline 

 forms. Spermatia oblong or subellipsoid, •oo2--oo3 mm. long 

 and •ooo5-"ooo7 mm. broad. 



On maritime rocks. Very abundant in one or other of 

 its forms all round the British Isles. In great profusion on 

 the short piece of Westmorland coast (vitelline form), both 

 forms occurring in the Isle of Man. 



Sometimes difficult, or almost impossible, to distinguish 

 from degraded forms of Lecanora murorum^ unless found 

 accompanied by plants showing the gradual degradation 

 from the type. 



5. Lecanora murorum (Hoffm., En., p. 62, tab. ix, fig. 2) ; Nyl. in 



Flora, 1883, p. 106. Placodium murorum Mudd, Man., 

 p. 132, pro parte; Leight., Lich. Flora, 3rd ed., p. 160, 

 pro parte. 



Exs. — Schar, 479 ; Hepp., 196, pro parte ; Mass., 97, 98. 

 Thallus closely adnate, rimoso-areolate at the centre, shortly 

 plicato-lobate at the circumference ; lobes crowded, short, 

 sometimes linear, but more frequently broadening anteriorly, 

 so as to assume a triangular outhne, flat or slightly convex, 

 thin or somewhat tumid, inciso-crenate at the apices which 

 are often thickened and incurved, rarely quite naked, most 

 frequently albo- suffused, pale yellow to reddish yellow ; 

 true colour often concealed beneath a thick white pul- 

 verulence. 



Apothecia small, deeply coloured, surrounded by an entire 

 paler margin of the same colour and consistence as the 



Naturalist," 



