200 LKCANO-LKCIDERI [lOPADIUM 



3. L. fecundum Th. Fr. Licli. Arct. p. 202 (I860).— Thallus 

 effuse, verrucose-granulose, the granules concrete, often subfur- 

 furaceous, brownish- or greenish-grey (K — , CaCl — ). Apothecia 

 small, sessile, appressed, black, at lirst concave, then somewhat 

 plane, the margin entire, at length excluded ; hypotheciuni 

 brownish or reddish-brown ; paraphyses slender, conglutinate, 

 blackish at the apices ; spores 8 in the ascus, oblong, often 

 narrowed at one or the other apex, 0,022-40 mm. long, 

 0,010-18 mm. thick; hymenial gelatine deep bluish with iodine. 

 — L. sociale Koerb. Parerg. Lich. p. 174 (1860). Biatora socialis 

 Hepp ex Koerb. I. c. Lecidea fecunda Nyl. ex Stiz. Lich. Helv. 

 p. 171 (1882) ; Cromb. in Grevillea xxii. p. 59 (non Leight. Lich. 

 Fl. ed. 3, p. 374, fide Cromb. MS.). L. socialis Cromb. in Journ. 

 Bot. XX. p. 275 (1882). 



Crombie in MS. notes has rejected Leighton's description and the 

 specimen collected near the Wrekin, Shropshire. I have not seen 

 the specimen. 



Hab. On dead mosses among rocks in an alpine locality. — Distr. 

 Very scarce on one of the S. Grampians, Scotland. — B. M. Summit 

 of Craig Calliach, Perthshire. 



Tribe XIX. G R A P H I D E I .—Nyl. in Mem, Soc. Sci. 

 Nat. Cherb. iii. p. 187 (1855) emend. 



Thallus shrubby or crustaceous, sometimes developed under 

 the bark (hypophloeodal), often little visible or wanting. Algal 

 cells (gonidia) Chlorophycese (TrentefoJdia or rarely Palmellacese). 

 Apothecia roundish or irregular (ardellse), or linear (lirellse), 

 immarginate or with a proper margin only. 



The Graphidei are distinguished by the presence of chryso- 

 gonidia (TrentepoJilid) in the thallus, and by the form of the 

 apothecia. There are six British Natural Orders : — 



DIRINACE^. — Thallus crustaceous, corticate on upper 

 surface. See DiRINA (Part I. pp. 490-491). 



ROCCELLACE^. — Thallus laciniate, strap - shaped or 

 roundish, corticate on both surfaces. See BOCCELEI (Part I. 

 pp. 181-184). 



LECANACTACE^. — Thallus crustaceous, not corticate. 

 Apothecia irregularly roundish, usually marginate. 



ARTHONIACE^. — Thallus crustaceous, not corticate. 

 Apothecia irregularly roundish, linear or stellate, immarginate. 



GRAPHIDACE^. — Thallus crustaceous, not corticate. 

 Apothecia linear, marginate. 



CHIODECTONACE^.— Thallus crustaceous, not corticate 

 Apothecia aggregate in stroma-like portions of the thallus. 



