I'l.ATvsMA.] muuui'i. 227 



Form 2. ainpullaceum ('romb. Linn. Soc. Juurp. IJot. xvii. 

 (1880) p. r)72. — 'riiullus vcsi(tuloso-inriuted eitlior towards the 

 apices of the luciiiiic. or Iutc and there tliroiifcliout. Apotliecia 

 never seen. — Lichen ainpullnrens Linn. Sp. ]*]. {Mo.i) p. 114(5; 

 Huds. Fl. Angl. p, 450 ; With. Arr. cd. 3, iv. p. Gl. Liclunouhs 

 timtoriurn (jlahnmi vesicidosuui Dill. Muse. 188, t. 24. f. H2. Li- 

 chenoides sdXdtile iinctoriuiii folils hifioribus iion jnlosis, vesiculas 

 proferens Dill, iu Kay, Syn. ed. '.i, p. 74, n. 71. 



A monstrosity, caused by the presence of the parasite Ahrothallm 

 Smithii. Tlie portions of the lacinife which are the host become more or 

 less biillato-inflatf'd (var. /y«//r//rt Sch.X'r. Enuni. p. 13). These •' inflated 

 vesicles" were mistaken by Dilleuius and older authors for apothecia. 



Ilah. On shady rocks in upl md situations. — Dkf.r. Local and scarce in 

 N. Enjrland (where it was originally detected near Coin, in Lancashire), 

 and amonir the N. Grampians.— B. M. : Craisr Cluny, Braemar, Aber- 

 deenshire. 



Yar. /?. tenuisectam Cromb. Grevillea xv. (18S6)p. 40. — Thallus 

 dark-glauooiis or brownish-black above, blackish beneath : lacinise 

 short, narrow, much divided and crowded. 



A distinct variety, presenting a panniform aspect. The darker colour 

 of the thidlus is probably owing to the habitat. It is seen only in a 

 sterile condition. 



Hiih. On exposed boulders in mountainous regions. — Disti: Rather 

 local, though not uncommon in W. England, X. Wales, among the 

 Grampians, and the N.W. Highlands of Scotland. — R ^L : Stiperstones, 

 Siiropshire; Clougha, Lancashire; Rhcwgreidden, Merionethshire. Crian- 

 larich and Ben Lawers, Perthshire; MoiTone, Braemar, Aberdeenshire; 

 Glen Nevis, Inverness-shire ; Hills of Applecross, Ross-shire. 



12. P. lacunosum Xyl. Mem. 8oc. Chcrb. v. (18.57) p. 100 ; 

 Syn.i.p.;314. — Thallus foliaceo-expanded,reticulato-lacanose, broadly 

 laciniate, or Liciniato-lobed, glaucescent or greyish-white, beneath 

 blackish or pale-brown towards the circumference; laciniie crenato- 

 undulate and incised, rotundate at the apices (K]}^^ ow.-sh^ CaCl~), 

 Apothecia elevated, moderate or large, reddish-brown, the margin 

 entire ; spores ellipsoid, 0,00(j-8 mm. long, (>, 004-5 mm. thick. — 

 Carx'oll, Journ. Bot. 18(^5, p. 288 ; Cromb. Lich. Brit. p. 27 ; Leight. 

 Lich. Fl. p. 103, ed. 3, p. 98. — Cetraria lucumsa Ach. Meth. (1803) 

 p. 295. 



Distinguish e<l from the preceding, some states of which it closely re- 

 sembles, by the much broader and rounded lacinine, with their reticu'lato- 

 rugose upper surface. The thallus is frequently more or less isidiiferous, 

 sometimes densely so, when growing iu moist places. On dry exposed 

 rocks it is of a dark-chestuut colour, as if it had been scorched. The 

 apothecia have not been found in this country, but the spermogones, 

 which are similar to those of PL ykiuciim, occasionally occur. 



Hah. On shady rocks iu subalpiue districts. — DMr. Local in the S.W. 

 and Central Highlands of Scotland, chiefly among the Grampians. — B.M. : 

 Glen Falloch. Ben Lawers, and Craig Calliach, Perthshire ; Craig Clunv 

 and Morrone, Braemar, Aberdeenshire: near Fort William. Inverness-shire. 



q2 



