VBERUCAEIa] VBKEDCAEIACBffi 289 



Considered by Nylander (I. c.) as closely allied to V. truncatula, a, 

 Pyrenean lichen. It strongly resembles V. coerulea, but with smaller 

 spores. 



Hah. On calcareous rocks. — B. M. Twelve Pins, Kylemore, 

 Connemara, Gralway. 



Form continuella Nyl. ex Shaokleton & Hebden in Naturalist, 

 1892, p. 17. — Thallus white, continuous. Specimen not seen. 

 Hab. On damp rocks (Malham, Yorkshire). 



30. V. glaucina Ach. Syn. p. 94 (1814). — Thallus glaucous 

 or leaden-grey, thickish, crustaceous-cartilaginous, deeply cracked- 

 areolate, determinate, the areolae smooth, plane, edged with the 

 predominant blackish hypothallus. Peritheoia blackish, immersed 

 one or more in each areola, sometimes confluent, the ostiole be- 

 coming somewhat prominent ; perithecial wall black, entire ; spores 

 ellipsoid, 0,010-20 mm. long, 0,005-8 mm. thick. — Leight. Lich 

 Fl. p. 423 ; ed. 3, p. 453. F. polystiota Borr. in Sm. Engl. Bot 

 Suppl. t. 2741 (1832) (text); Tayl. in Mackay Fl. Hib. ii. p. 94 

 Leight. Angioc. Lich. p. 49, t. 21, fig. 5 & Lich. Fl. p. 422 

 ed. 3, p. 453; Cromb. Lieh. Brit. p. 111. V. viridula var 

 glaucina Ach. Lich. Univ. p. 675 (1810); Oromb. Lich. Brit, 

 p. 111. V. fuscella var. glaucina Schser. Enum. p. 215 (1850) 

 Mudd Man. p. 289. Lithocia glaucina S. F. Gray Nat 

 Arr. i. p. 497 (1821). Endocarpon polystictum Borr. I. c. 

 (plate). 



Exsicc. Larb. Lich. Hb. n. 238 (as V. polysticta). 



Often confused with V. fuscella on account of the predominant 

 hypothallus which is visible more or less through the cracks of the 

 grey thallus and gives the whole plant a dark appearance. 



Hab. On calcareous rocks and walls. — Distr. Not uncommon in 

 the Channel Islands and S. England, rare in N. and W. England, also 

 recorded from N. and S.W. Ireland.— -B. M. Alderney ; Plymouth, 

 Devon ; Little Danny, Glynde, Hurst and Falmer, Sussex ; Lucoomb, 

 I. of Wight ; Lenha,m, Kent ; St. Vincent's, near Bristol, Gloucester- 

 shire ; Llanymynaoh, Shropshire ; Safiron Walden, Essex ; North- 

 ampton ; Bilsdale, Yorkshire ; near Cromer, Norfolk ; near Stanhope, 

 Durham. 



Subsp. canella A. L. Sm. — Almost similar to the species 

 but with larger somewhat fusiform spores, colourless, becoming 

 brownish, 0,025-32 mm. long, 0,007-011 mm. thick. — Verrucaria 

 canella Nyl. in Flora Ixvi. p. 102 (1883) ; Oromb. in Grevillea 

 xii. p. 91. Specimen not seen. 



Hab. On calcareous rocks. — Distr. Bare in N. Wales (Bangor, 

 Carnarvonshire) . 



31. V. fuscella Ach. Lich. Univ. p. 289 (1810).— Thallus 

 dark-grepsh-brown, thickish, cartilaginous, deeply cracked- 

 areolate, the areolse smooth, bordered with black from the 

 predominant hypothallus, determinate, Perithecia minute, im- 



II. u 



