J. A. MARTINDALE : NOTES ON BRITISH LICHENS. 



357 



2. Lecanora dissidens Nyl. in Flora, 1875, p. 298 ; Leight., Lich. 



Flora, 3rd ed., p. 161 (as a form of L. 7?iuroriwi) ; Lichen 

 flavicans Withering, Arr., ytli ed., vol. iv, p. 21 (fide 

 Crombie in Grevillea, vol. xii, p. 61). 



Thallus appressed, laciniate ; lacinige radiating, discrete or sub- 

 discrete, linear, •25-1-0 mm. broad, flat or slightly convex, 

 torulose, multifid, slightly rough on the upper surface, 

 vitelline or sub-miniate. 



Apothccia having the disc deeper coloured than the thallus, plane 

 almost from the first, surrounded by a paler border, which, 

 at first entire, becomes crenulated or jagged when old. 

 Paraphyses stoutish, articulate, often much branched from 

 the middle upwards, upper cells swollen. Spores ellipsoid, 

 •oo9-'oi6 mm. long and •oo5-'oo7 mm. broad. 



SperjHOgonia very minute and difficult to detect. Spermatia 

 borne on arthrosterigmata, straight, rod-like, •oo2-'oo3 mm. 

 long and ■ooo5-*ooo6 mm. broad. 

 On rocks, walls, and tiled roofs. 



Distribution not made out, but probably widely diffused. 

 Nylander founded the species on plants gathered near 

 Cirencester by Mr. Joshua. Distributed through West- 

 morland from Arnside in the south to Eamont Bridge in 

 the north. In some places abundant on roofs of farm- 

 buildings. 



3. Lecanora scopularis Nyl. in Flora, 1883, p. 105. 



Exs. — Norrlin, H. L. F., 280; Fries and Stenh., 391a. 



Thallus small, closely adnate, lobato - laciniate ; segments 

 radiating, hardly discrete, linear, -25 mm. broad, somewhat 

 rigid, convex, naked, vitehine or subminiate. 



Apothicia concolorous with the thallus, border entire. Para- 

 physes slender, branched, the upper cells gradually increasing 

 in width, but not to such a degree as in the two preceding 

 species or in miirorii7n^ apical cells oblong or subspherical, 

 •oo3-'oo5 mm. broad. Spores elhpsoid, •oo9--oi7 mm. long 

 and ■005--007 mm. broad. 



Spermogonia minute. Spermatia ' -0025 mm. long and 

 •ooo5-'ooo6 mm. broad,' Nyl., I.e. 



On maritime rocks, Portlethen, Kincardineshire (Cromb.). 

 I have only seen continental specimens gathered near 

 Viborg by Wainio, and kindly sent me by Prof. Norrlin, of 

 Helsingfors. These specimens, unfortunately, are without 

 spermogonia. 



Dec. 1887. 



