224 GRAPHIDEI [XILOGKAPHA 



indicated merely by scattered gonidia among the fibres of the 

 substratum. 



Hab. On old fir palings in upland tracts of mountainous districts. 

 — Distr. Seen only from among the Grampians, Scotland, where 

 it is not infrequent. — B. M. Glen Orchy, Argyll ; Glen FaUoch, 

 Glen Lochay, Ben Lawers, Pass of Killiecrankie, and Glen Fender, 

 Perthshire ; Crathie, Braemar, Aberdeenshire ; Eothiemurchus Woods, 

 Invernessshire. 



Tar. pallens Xyl. in Mem. Soc. Cherb. v. p. 128 (1857). — 

 Thallus as in the species. Apothecia rather smaller, pale or 

 pale-brown. — Cromb. in Grevillea i. p. 173 ; Leight. Lich. PI. 

 ed. 3, p. 391. 



Differs only in the paler colour of the apothecia, though at times 

 they are here and there concolorous with those of the type. 



Hah. On old fir palings in mountainous districts. — Distr. Found 

 sparingly in a f ew locaJities among the S. Grampians, Scotland. — B. 1[. 

 Achmore, Glen Lochay. T\il1in and Pass of Killiecrankie, Blair 

 Athole, Perthshire. 



Form elliptica Xyl. ex Cromb. in Journ. Bot. xi. p. 135 

 (1873) nomen; Leight. Lich. Fl. ed. 3, p. 391 (1879). Apothecia 

 shorter, oblong or difform, blackish or brown. — X. seaphoidea 

 Stirton in Grevillea iii. p. 35 ; Leight. Lich. Fl. I. c. 



Differs in the form of the apothecia, which vary also in colour 

 according to age and exposure. 



Hab. On old palings and denudate trunks of trees in mountainous 

 regions. — Distr. Here and there among the Grampians, Scotland. — 

 B. Af. Achmore, Trillin , Ben Lawers and Pass of Killiecrankie, Perth- 

 shire : Crathie, Braemar, Aberdeenshire ; Eothiemurchus, Invemess- 

 shire. 



■2. X. laricicola Nyl. in Flora Iviii. p. 13 (1875).— Thallus 

 effuse, very thin, greyish- white (K — , CaCl — ), often scarcely 

 visible. Apothecia superficial, minute, oblong or slightly flexuose, 

 at length somewhat applanate with evanescent margin, black, 

 opaque, within whitish ; epithecium brown ; paraphyses absent 

 or abnormal (membranaceous) ; hypothecium brown ; spores 

 ellipsoid, 0,012-15 mm. long, 0,007-8 mm. thick; hymenial 

 gelatine tawny- wine-coloured with iodine. — Cromb. in GreviUea 

 iii. p. 128; Leight. Lich. FJ. ed. 3, p. 391. 



Exsicc. Cromb. n. 97. 



Interesting as occurring on living trees. The apothecia are some- 

 what irregularly scattered. 



Hab. On the bark of an old larch tree, near its base, in an upland 

 mountainous region. — B. M. Ben Lawers, Perthshire (the only 

 locality). 



3. X. spilomatica Th. Fr. Lich. Scand. p. 639 (1874).— 

 Thallus effuse, greyish-white, thinnish, with numerous yeUowiah- 

 green soredia (K — , CaCl — ). Apothecia erumpent, subminute. 



