LECANOKA.] LECANO-LECIDEEI. 471 



Chesil Beach, Portland Island, Dorsetshire ; Lyndhurst Moor, Hants ; 

 Thetford Warren, Norfolk ; Hereford Beacon, Malvern, Worcestershire ; 

 Crossfaen, Monmouthshire ; Caer Caradoc and Longmyud, Shropshire ; 

 Eglestone, Durham. Appin, Argyleshire. 



Var. /3. zonata Wainio, Medd. Soc. pro F. et PI. Fenn. t. vi. (1881) 

 p. 168. Thallus determinate, thinly rimoso - areolate, greyish 

 glaucous, effigurate at the circumference with concentric and 

 parallel paler lines and limited by a very thin, black hypothallus. 

 Apothecia as in the type. Cromb. Grevillea, xix. p. 57. Sagedia 

 zonata Ach. Vet. Ak. Handl. (1809) p. 165 ; Lich. Univ. p. 329. 



A distinct variety, usually overlooked by authors, but well charac- 

 terized by the thallus being more or less broadly zonate at the circum- 

 ference. The lines with which it is there marked are at times whitish, 

 as stated by Acharius, but this apparently is the result of abrasion. A 

 young and less developed condition may be var. squamata (Flot.) Fr. fil. 

 Lich. Scand. p. 276 (non Leight. Lich. Fl. ed. 3, p. 194, which is only 

 the so-called form porinoidea hypothalline). 



Hub. On siliceous stones in maritime and upland situations. Distr. 

 Extremely local and scarce in S.E. England. B. M. : Lydd Beach, 

 Kent ; South Downs, Sussex. 



Yar. y. lusca Nyl. Pyr. Or. Obs. Nov. (1891) p. 59 (nota 1). 

 Thallus thinnish, rimoso -areolate, subrugulose, greyish or dark- 

 grey ; hypothallus little visible. Apothecia somewhat small, often 

 flexuose; spores 0,016-21 mm. long, 0,010-16 mm. thick. 

 Lecanora lusca Nyl. Flora, 1873, p. 69 (nota 1); Cromb. Journ. 

 Bot. 1882, p. 274 ; subsp. lusca Cromb. Grevillea, xix. p. 57. 



Now viewed by Nylander as only a variety of L. gibbosft, differing in 

 the characters given and more especially in the rather longer spermatia, 

 which are 0,016-21 mm. long, 0,010-14 mm. thick. In other respects it 

 approaches subspecies L. subdepressa. The small apothecia are at times 

 numerous, crowded, and diftbrm. 



Hab. On rocks in maritime and mountainous districts. Distr. Only a 

 few localities in Great Britain and the Channel Islands. B. M. : Chateau 

 Point, Isle of Sark. Breidden mt., Montgomery j Barmouth, Merioneth- 

 shire ; near Newton, Cleveland, Yorkshire ; Scale Hill, Lazonby, 

 Cumberland. Ben Lawers and Craig Calliach, Perthshire ; S. of Bay of 

 Nigg, Kincardineshire. 



Subsp. 1. L. depressa Nyl. Not. Siillsk. pro F. et Fl. Fenn. n. s. 

 v. (1866) p. 137. Thallus effuse, areolato-rimulose, greyish or 

 dark ; hypothallus indistinct. Apothecia somewhat small, subleci- 

 deine, at length plane ; spores 0,018-24 mm. long, 0,008-0,014 mm. 

 thick. Cromb. Lich. Brit. p. 55; Leight. Lich. Fl. p. 210 proparte, 

 ed. 3, p. 194 pro parte. According to Th. M. Fries (Lich. Scand. 

 p. 282) this is not Sagedia depressa Ach. (Lich. Univ. p. 327, 

 t. 6. f. 3), which has thalline reaction K+ and is a form of 

 L. cinerea. 



Well characterized as a subspecies by the type of the apothecia, which 



