208 Rev. AV. A. Leighton on the British Graphidese. 



variable in size and shape, simple or branched in an irregular 

 substellate manner. Proper margins rounded, thickened and 

 inflexed, enclosing the disk, which is variable in its expansion, 

 either rimseform or broader and canaliculate. 



11. Opegrapha vulgata, Ach. Thallus effuse, cartilagineo- 

 membranaceous, cracked and scaly, greenish white ; lirellfe pro- 

 minent and sessile, variable in size, shorter ones roundish or ob- 

 long, longer ones slender and linear, simple, wavy and shining 

 or greasy ; disk rimaiform, uniform ; proper margins thick, very 

 round and inflexed; sporidia in asci, eight, fusiform, 5 -septate, 

 pale yellow. 



a. vulgata. Lirellse small, numerous, but regularly scattered ; 

 disk rimseform, more or less expanded. 



Lichen vulgatus, Ach. Prodr. 21 (excl. syn.) (1798). 



Opegrapha vulgata, Ach. Meth. 20 (1803) ; L. Univ. 265; Syn. 73 (secun- 



diun specimina Cel. Swartzii " cum Acliario seipso collecta " in herb. 



Borrer ! ; Sm. E. Bot. t. 1811 ; Mart. Fl. Erlang. 279 ; Hook. Fl. Scot. 



2. 43, Brit. Fl. 2. 145 ; Grev. Fl. Edin. 352 ; Chevallier, Graphid. 32. 



t. 6. f. 5c; Wahl. Fl. Suec. 860; Fingerh. Fl. Eiffl. 22; Tayl. Fl. 



Hib. 2. 106; Bohler, Lich. Brit. no. 127 ! 

 Graphis atra (in part), Meyer in Sprang. Syst. Veg. 4. 1. 251 (1827). 

 Opegrapha notha, Johnst. ! Fl. Berw. 2. 100 (1831). 



— ■— atra, ^. vulgata, Scha;r. Spicil. 325 (1836) ; Enum. 154 ; Exsic. 516 ! 

 atra, a. stenocarpa (in part). Fries, L. Ref. 367 (1831); Summa V. 



S. 118 ; Tuckermann, N. Amer. Lich. 75. 

 Graphis vulgata, ^. periblastetica, Wallr. Crypt. Germ. 327 (1831). 



On fir, ash, beech, apple, holly. Hurst and St. Leonard's 

 Forest, Sussex ! Mr. Borrer. Lasswade ! and near Edinburgh ! 

 Dr. Greville. Malvern Hills, Worcestershire ! Mr. E. Lees. 

 Portslade, Sussex ! Mr. Borrer, Berwick-on-Tweed ! Dr. G.John- 

 ston. Haughmond Hill, Shropshire ! near Shrewsbury ! Pen 

 Maen Mawr, Caernarvonshire ! 



Thallus effuse, thin, membranous, cracked and scaly, subpul- 

 verulent and scurfy, of a pale dirty white tinged slightly with 

 green, sometimes quite smooth and continuous ; and in other 

 specimens white, canescent, entirely pulverulent. LirelliB nume- 

 rous but regularly scattered, sessile and prominent, vai'iable in 

 size, though chiefly small and short, roundish, oblong and 

 linear, of a plump turgid appearance, black and shining, straight 

 or curved. Not unfrequently there are longer lirellse inter- 

 mixed and approaching in size and flexuosity to those of steno- 

 carpa, so that it is difficult to say to which variety such speci- 

 mens should be correctly referred. On these sjjecimcns, and 

 more especially in the variety stenocarpa, the lirellse are exceed- . 



