LEPROCATJLON.] STEREOCAULEI. ] 23 



30. LEPROCAULON Nyl. ex Lamy, Bull. Soc. Bob. Fr. t. xxv. 

 (1878) p. 352. Thallus minute, subpodctiform, subleproso-granu- 

 lose, not bearing cephalodia, the pseudo-podetia csespitosely con- 

 gested, simplish. Apothecia and spermogones unknown. 



This pseudo-genus, containing a single species, separated by Nylander 

 from Stereocaulon, is but a fruticulescent Lepraria, It may be placed 

 here on account of its superficial resemblance to Stereocaulon, to which, 

 however, it is not even allied (vide Flora, 1876, p. 578). 



1. L. nanum ftyl. ex Lamy, ?. c. Thallus minute, leproso-granu- 

 lose at the base ; granules very small, glaucous-white or subaerugi- 

 nose ; pseudo-podetia very short, slender, filiform, ca3spitoso-con- 

 gested, somewhat simple or sparingly divided towards the apices, 

 the branches often subfastigiate, obsoletely arachnoid, often glabrous 

 (K ). Cromb. Grevillea, xv. p. 15. Stereocaulon nanum Ach. 

 Meth. (1803) p. 315; Gray, Nat. Arr. i. p. 411 ; Sm. Eug. Fl. v. 

 p. 233 ; Mudd, Man. p. 67; Cromb. Lich. Brit. p. 17; Leight. Lich. 

 Fl. p. 80, ed. 3, p. 73. Brit. Exs. : Larb. Lich. Hb. n. 284. 



" Stereocaulon nanum is not a Stereocaulon, but, so far as I have seen in 

 nature, only a Lepraria (Leprocaulon). The thallus is imperfect, and it 

 has no right to be referred to Stereocaulon " (Nylander in lift.). This 

 view is confirmed by the absence of the yellow reaction with K, charac- 

 teristic of that genus. 



Hub. In crevices of rocks and walls in maritime and mountainous dis- 

 tricts. Distr. Local, though plentiful where it occurs, in the Channel 

 Islands, N. Wales, W. and N. England, amongst the Grampians, Scot- 

 land, and rare in N.W. Ireland. B. M. : Boulay Bay, Island of Jersey ; 

 Island of Guernsey. Near Kingsbridge and Totness, Devonshire ; La- 

 morna and Helminton, Cornwall: near Alfrick, Worcestershire; Oswestry, 

 Shropshire; Bettws-y-Coed, Carnarvonshire; Aberdovey, Merioneth- 

 shire ; Teesdale, Durham. Barcaldine, Argyleshire ; Balmerino, Fife- 

 shire ; Glen Lochay, Perthshire ; Den of Balthayock and Reeky Linn, 

 Forfardhire ; Falls of Lui, Braemar, Aberdeenshire. Learmont, co. Derry. 



Tribe VI. CLADONIEI ffyl. Mem. Soc. Cherb. ii. 

 (1854) p. 11 ; Syn. i. (I860) p. 186. 



Thallus foliose, fruticulose or caespitose, erect or ascending, con- 

 sisting of fistulose or subfistulose podetia, with usually a gonidial- 

 cortical layer, and generally also of horizontal leaflets or squa- 

 mules at the base, sometimes also on the podetia, containing gonidia 

 and corticate only above, or very rarely of crustaceous basal gra- 

 nules ; medullary layer formed principally of filamentose agglu- 

 tinate longitudinal elements. Apothecia cephalodine or biatorine, 

 typically terminal on the podetia, rarely affixed to the leaflets, often 

 aggregate (" symphicarpous "), variously coloured (not black) ; spores 

 81133, simple, oblong, small, colourless ; paraphyses somewhat short, 

 occasionally bifurcate. Spermogones generally protuberant on the 

 podetia ; sterigmata slender, simple or sparingly branched. 



