Rev. W. A. Leighton on the Lichens of Cader Idris. 199 



h'fliophila, Ach., L. fuh'i/iiiosa, Tayl., L. concretely Wliliib., 

 Cladonia cerciconiis, Ach., of immense size and in magnificent 

 fructification, Stereocaulon denudatum, Flk., Placojysis cjelida^ 

 (L.), Lecanora atra (L.), L. lencoiyhaxi^ Flk., Lecanora hifor- 

 migera^ Leight., in beautiful condition, Spilonema pai-adoxum^ 

 Born (sterile), and a eiu'ious composite Sj)h(prta growing pa- 

 rasiticallj on tlie tliallus of Parmelia saxatiUs^ L., having 

 spores 8, fuscous, faba^form or subelliptical, 3-septate. 



The following day (Tuesday) we ascended the pass to the 

 " Giant's Pebbles," on which I collected Lecidea ricsticula, 

 Nyl., L. fuUginosa.) Tayl., Lecanora leucophiva^ Flk., and 

 Pilophor on fibula, Tuck., new to Great Britain, and only before 

 known as occurring in the White Mountains, North America. 

 Thence over Geu Craig, where I gathered Lecidea contiguay 

 Ach.,f. hydrophila. Descending on the north side to Llyn Aran, 

 we found Stereocaulon cereolinum, a minor state of S. con- 

 densatum, Hffm., Verrucaria irrigua, Tayl., Lecidea pha^ops^ 

 NyL, and Ij.jurana, Sch?er. Time pressing, we could not delay, 

 but scrambled again to the summit, and descended by a very 

 formidable descent over projecting rocks and loose " screes," 

 interspersed with safe grassy patches down the precipices 

 north of the lake into Llyn Cae, and so by the ton-ent-side 

 to Minfibrd. This was rather a day of scrambling than of 

 collecting ; but we determined to devote Wednesday entirely to 

 Llyn Cae, where my gatherings were Lecidea contigua, Ach., 

 f. oxydata (K — C — ), L. fuliginosa, Tayl., L.jurana, Scluer. 

 (K- C-), L. anqjhihia, Fr. (K+ C + ), L. phaia, Ach.? 

 (K — C — ), L. rimdosa, Ach. (K + ), L. lapicida, Fr., var. de- 

 clinanSy Nyl. (K + ), L. p)etrcea, Flot., L. geographicay L., L. 

 phaopsy Nyl. (K+ C + ), L. ptanceola, A.c\\. (K yellow, C red), 

 L. consentiensy Nyl. (K— C — ) (new to Wales), Lecanora 

 cinerea (L.) (K + ), and its iorrw Acharii, E. Bot. 1087, L. 

 leucopho'ay Flk., L. hiformigeroy Leight. (K+ C + ), Placopsis 

 gelida (L.) (K yellow, C red), Opegrapha iesse/-rt/a(L)C.)(K-|- ), 

 Urceolaria scruposa, Ach., Lecanora atra, Ach. (K + ), Endo- 

 coccus perpusilluSyl^yl.y Verrucaria irrtguayTayl., I^ilophoron 

 fibuhy Tuck., in magnificent profusion, and a new species of 

 Lecideay which I name plicatilisy and describe below. 



Thui-sday being the tether of our trip, we returned home- 

 wards. 



Lecidea pana-ola, Ach., is well represented in Fellm. Lieh. 

 Lapp. Or. 182 ! Seller. L. llelv. 469 ! and Anzi, Lich. Langob. 

 83 ! Its chemical reaction is K yellowish, C red. It is figured 

 under the name oi' athroocarpa in K. Bot. 1829. Mr. Borrer's 

 Herbarium at Kew contains it from Cader Idris, by Dickson 

 named " Z. niveo-afcr, Dicks.," also from "rocks above 



