LKCANOKA.] LECANO-LECIDEEI. 425 



105. L. Zosterae Nyl. Flora, 1876, p. 577. Thallus effuse, very 

 thin, glaucous-grey, subevanescent (K , CaCl ). Apothecia 

 minute, plane, scattered or aggregate, reddish-brown, naked or 

 slightly pruinose ; the thalline margin thin, entire or subcrenate, 

 white-pulverulent: spores 0,011-14 mm. long, 0,006-7 mm. thick; 

 paraphyses very slender, discrete ; hymenial gelatine persistently 

 bluish with iodine. Lecanora umbrina subsp. Zosterce Nyl., Cromb. 

 Jouru. Bot. 1874, p. 148 ; forma Zosterce Leight. Lich. Fl. ed. 3, 

 p. 191. Lecanora subfusca var. y. Zosterm Ach. Syn. (1814) p. 158. 



Allied to L. umbrina, but differs in the pulverulent thalline margin of 

 the smaller apothecia, the size of the spores, the slender paraphyses, and 

 the reaction of the hymenial gelatine. It may be recognized from its 

 peculiar place of growth, though Nylander (Flora, /. c.) says that 

 L. Hageni also occurs zostericolous in Jersey. 



Hub. On old leaves of Zostera marina in maritime districts. Distr. 

 Sparingly in the Channel Islands, S.W. England, and S.W. Ireland. 

 B. M. : La Moye, Island of Jersey ; The Eperquerie, Island of Sark ; 

 Moulin Huet Bay, Guernsey. Pentire and the Lizard, Cornwall. Kil- 

 kee, co. Clare. 



106. L. Hageni Ach. Lich. Univ. (1810) p. 367(excl. vars.) ; Nyl. 

 Flora, 1872, p. 250. Thallus effuse, very thin, leproso-verruculose, 

 greyish-white, often nearly obsolete (K , CaCl ). Apothecia 

 small, plane or at length convex, pale- or dark-brown, naked or 

 cresio-suffused ; the thalline margin thin, subpersistent, crenulate or 

 subentire, white ; spores 0,009-11 mm. long, 0,005-6 mm. thick; 

 paraphyses thickish, jointed, brownish at the apices ; hymenial 

 gelatine bluish, then sordid wine -coloured with iodine. Leight. 

 Lich. Fl. p. 208, ed. 3, p. 192. L. umbrina var. Hageni Cromb. 

 Lich. Brit. p. 51. L. albella j. Hageni Mudd, Man. p. 148. 

 Lichen Hageni, Ach. Prodr. (1798) p. 57. Brit. Exs.: Larb. Lich. 

 Hb. nos. 131, 219. 



A plant not rightly discriminated by most authors from L. umbrina. 

 Among other marks of distinction, however, as well as in general aspect, 

 it at once differs from this in the shorter spermatia, as pointed out by 

 Nylander, /. c. These he gives in litt. as being 0,011-15 mm. long, 

 0,0005 mm. thick. The thallus frequently spreads extensively, and is 

 occasionally scarcely visible from the numerous crowded apothecia. These 

 at times become convex with the thalline margin excluded. 



Ilab. On trunks (usually decorticated) of trees, old pales, very rarely 

 on schistose rocks, from maritime to upland tracts. Distr. Not uncommon 

 in England, rare in Scotland, Ireland, and the Channel Islands ; not seen 

 from Wales. B. M. : St. Aubin's Bay, Island of Jersey. Lyndhurst, New 

 Forest, Hants ; near Hyde, Isle of Wight ; Wellow, near Bath, Somerset ; 

 Windsor Great Park, Barks; Brandon, Suffolk; Whnpole Park, Cam- 

 bridgeshire; Ayton, Cleveland, Yorkshire; Ennerdale, Cumberland. 

 Inverary, Argyleshire ; Achmore, Killin, Perthshire; Portlethen, Kin- 

 cardineshire (saxicolous). Castlemartyr, co. Cork; Ballynagarde, co. 

 Limerick. 



