IECIDEA] LBCIDEACEiE 75 



slightly concave with a thin prominent margin; hypothecium 

 pale or brownish; paraphyses loosely coherent, blue-greenish- 

 black or dark-brown at the apices; spores ellipsoid, 0,009-13 

 mm. long, 0,004-6 mm. thick ; hymenial gelatine blue then 

 sordid with iodine.— Mudd Man. p. 209 pro parte ; Cromb. Lich. 

 Brit. p. 81 pro parte (excl. vars.) ; Leight. Lich. Fl. p. 284 (excl. 

 vars.); ed. 3, p. 289 (excl. var.). L. polycarpa Moerke ex 

 Sommerf. Suppl. PI. Lapp. p. 149 (1826); Cromb. Lich. Brit, 

 p. 82 ; Leight. Lich. Fl. p. 283 ; ed. 3, p. 288. Lichen lapicida 

 Ach.- lich. Suec. Prodr. p. 61 (1798). 

 Exsicc. Johns, nos. 350, 387. 



Th. Pries (Lich. Scand. pp. 491, 493) places L. polyewrpa under 

 i. pantherma, of which he regards L. lapicida as a subspecies. 

 The only difference between the two is in the reaction with potash ; 

 in L. polycarpa the reaction varies from yellow to yellow followed 

 by red, while in L. lapicida there is usually no colour-reaction. 

 Pries further states that some specimens of lapicida give no reaction 

 in one part of the thallus, while in another they tinge red. The 

 reaction of our specimens varies from a faint yellow to crimson. 



nab. On granitic and schistose rocks. — Disir. Found chiefly in 

 mountainous regions. — B. M. Cader Idris, Merioneth ; Llyn Geironydd, 

 Trefriw ; Nant Prancon and Llanberis, Carnarvonshire ; Morrone, 

 Braemar, Aberdeenshire ; coast of Kincardineshire. 



Var. decliuans Nyl. Lich. Scand. p. 226 (1861).— Similar to 

 the type but with a darker hypothecium and nearly ecrustaceous 

 thallus (K+ yellow, then red). — Leight. in Ann. Mag. Nat. Hist, 

 ser. 3, xix. p. 403 (1867) ; Cromb. Lich. Brit. p. 81. L. polycarpa, 

 var. decUnans Leight. Lich. Fl. p. 284 (1871); ed. 3, p. 289. 

 L. decUnans Nyl. in Flora Ixi. p. 243 (1878). 



Eab. On rocks in mountainous regions. Specimen not seen. — 

 B. M. Two doubtful specimens without spores from Ben Lawers, 

 Perthshire, and Braemar, Aberdeenshire, collected and named by 

 Carroll. 



128. L. lithophila Ach. Syn. p. 14 (1814).— Thallus tar- 

 tareous, whitish or ashy-grey, thin, cracked-areolate, the areolae 

 plane (K— , CaCl — ); hypothallus black. Apothecia numerous, 

 moderate in size or small, scattered or aggregate and angular, 

 plane, brownish-black, velvety and soft, with a thin prominent 

 flexuose margin; hypothecium colourless or pale; paraphyses 

 slender, loosely coherent, sometimes with a greenish tinge, 

 clavate, and blackish-brown at the tips ; spores ellipsoid, 0,009-12 

 mm. long, 0,005-6 mm. thick ; hymenial gelatine deep-blue with 

 iodine. — Cromb. Lich. Brit. p. 82 ; Leight. Lich. Fl. p. 285 ; ed. 

 3, p. 290. 



Exsicc. Cromb. n. 183. 



Spores rarely well developed. Differs from other species in the 

 same group in the black velvety apothecia and the thickened apices 

 of the paraphyses. When the apothecia are very small and the 

 thallus almost evanescent it is f. minor Cromb. MS., two specimens 



