pykenula] pykenulacb^ 341 



Journ. Bot. i. p. 79 (1801) ; Grev. Fl. Edin. p. 353 ; Borr. in Engl. 

 Bot. Suppl. t. 2607, fig. 1 ; Hook, in Sm. Engl. El. v. p. 149 ; 

 Tayl. in Mackay Fl. Hib. ii. p. 87 ; Leight. Angioc. Lich. 

 p. 35, t. 15, fig. 3 & Lich. Fl. p. 447 ; ed. 3, p. 478 ; Cromb. 

 Lich. Brit. p. 118. V. glahrata Carroll in Journ. Bot. iii. p. 293 

 (1865) (non Ach.) ; Cromb. Lich. Brit. p. 118 pro parte ; Leight. 

 Lich. Fl. p. 448 ; ed. 3, p. 479. 



Exsicc. Larb. Lich. Csesai-. n. 48 ; Leight. n. 27 ; Bohl. 

 n. 106. 



The thallus is often punctuated by clear white dots, a growth 

 character not always present. The specimens of " V. glahrata " 

 collected by Carroll all belong to this species ; they differ only in the 

 absence of the white dots on the thallus. 



Sah. On the bark of trees. — Distr. Frequent in the Channel 

 Islands, England and Wales, somewhat rare in Scotland and Ireland. 

 — B. M. Jersey ; Sark ; Withiel, Cornwall ; near Plymouth, near 

 Totnes and Torquay, Devon ; I. of Wight ; Dorset, New Forest, 

 Hants ; Arundel Park and Henfield, Sussex ; Leigh Woods, Bristol, 

 Somerset ; Gosfield Hall Woods, Ulting, Massing and Great Braxted, 

 Essex ; Church Stretton, Shropshire ; Harlech and Dolgelly, Merioneth ; 

 Gloddaeth near Conway and Bettws-y-Coed, Carnarvonshire ; Kildale, 

 Cleveland and Bilsdale, Yorkshire ; Largo, Ayrshire ; Achosragan 

 Hill and Barcaldine, Argyll ; Glen Falloch, Perthshire ; Ballyedmoud, 

 Cork; Derrycuintry, Cromaglown and Tore Mts., Glencar, Killarney ; 

 Lough Inohiquin, Kerry; Glenstale, Tipperary; TuUy, Connemara, 

 Gal way. 



Form elseodes A. L. Sm. — Thallus dark blackish or purplish- 

 brown, resembling a diffuse dark oily stain. — Verrucaria nitida, 

 f. elseodes Leight. Lich. Fl. ed. 3, p. 479. 



Hab. On old laurel and other trees. — Distr. Bare in N, Wales. — 

 B. M. Bettws-y-Coed, Carnarvonshire. 



Var. nltidella Mudd Man. p. 299 (1861).— Thallus thin, 

 yellowish or brownish. Perithecia smaller than in the species, 

 entirely immersed or more or less uncovered, the ostiole a small 

 pore not always visible. — Var. dermatodes Mudd I. c. Verrucaria 

 dermatodes Borr. in Engl. Bot. Suppl. t. 2607, fig. 2 (1829); 

 Hook, in Sm. Engl. Fl. v. p. 149 ; Tayl. in Mackay Fl. Hib. ii. 

 p. 87. Y. nitida var. dermatodes Leight. Angioc. Lich. p. 36, 

 t. 15, fig. 4 (1851). V. nitida var. nitidella Floerke ex Nyl. in 

 Maine et Loire Mem. See. Acad. iv. p. 46 (1858) ; Cromb. Lich. 

 Brit. p. 118 ; Leight. Lich. Fl. p. 448; ed. 3, p. 479. V. aehro- 

 spora Nyl. in Flora I. p. 179 (1867). F. glabratula Nyl. torn, 

 cit. p. 330. V. glahrata var. glabratula Carroll in Journ. Bot. v. 

 p 260 (1867); Cromb. Lich. Brit. p. 118; var. dermatodes 

 Leight. Lich. Fl. p. 449 (1871) ; ed. 3, p. 480. 



Exsicc. Larb. Lich. Csesar. n. 99 & Lich. Hb. n. 359 ; Leight. 

 n. 28 ; Baxt. Stirp. Crypt n. 73. 



The perithecia are somewhat more persistently immersed than in 

 the species ; the smaller size in extreme forms represents almost a 



