Lccidea.] LICHENES. 173 



upothecia minute very numerous roundish black (often brown- 

 red) with a white border incorporated with the crust. S,/t. 



Ach. Syn. p. 137.— Lecanora cyrtttspis, Ach. Lick. Univ. — 



Lichen punctatus, Dicks. — E. Bot. t. 450. 



On rocks and stones, frequent. — The colour of the Mir. «. of this 

 Lichen, on which it chiefly depends for its character, seems to me to 

 be owing to the oxyde of iron, which tinges other species growing on 

 the same stones. I follow Acharius in making the V. punctat. a var. 

 of it : but if either be really distinct from V. cinerea or calcarea, I 

 should prefer considering the var. £. the type of the species. 



6. U. rufescens, (reddish Urceolaria); crust indeterminate 

 thin tartareous tessellated brown, apothecia small dark-chestnut 

 immersed at length flat with an elevated entire margin. Borr. 

 — Sagedta rufescens, Ach. Syn. p. 135. — Lccidea rufescens, Borr. 

 in E. Bot. Suppl. t. 2657. 



Rare. On sandstone (walls?) at Gorleston, Suffolk, Mr. D. Turner. 

 — Mr. Borrer remarks that this approaches in structure the Lccidea 

 cechumena, £. athroocarpo, which indeed corresponds in its sunken shields 

 with some Acharian Urceolarice. " We do not understand satisfactorily," 

 sa\ s Mr. Borrer, " the distinction between the Acharian genera Urceolaria 

 and Sagedia t and since every gradation is to be found, among the crus- 

 taceous Lichens, between completely immersed and completely protu- 

 berant apothecia, it is perhaps best to refer, for the present, to Lccidea, 

 all those species in which the apothecium has a proper margin, whether 

 it be or be not, surrounded by an accessory margin from the thallus." 



0, iS — Mr. Borrer, in a list of species of certain British genera of Lichen* 

 which he has been so good as to communicate to me, enumerates 4 

 of the Acharian Genus Gyalecta ; but none is figured in K. But., and 

 Acharius alone seems to be the authority for two (G. epulotica and G. 

 celhalea). I am myself unacquainted with them : and the obser- 

 vations of Mr. Borrer will, I think, justify me in not introducing them into 

 our British list. Of the 4 species he Bays :"1. G.epulotica, Ach. Syn. p. !>• 

 I am bo imperfectly acquainted with this as not to know how it ditlers 

 from Urceolaria Acharii, notwithstanding Acharius' u toto catloabha 

 Hncta." >. G. bryophOa, Ach. Sun. p. «>. I still regard thi- as a state of I '. 

 tcrupota, (under which plant it is quoted). 3. G. M'ahlcnbcriiuuui, 

 p>. Ach. Si/n. />. '.>. We have on Kims iu SuSSei what I suppose t 

 this, hut I am doubtful whether it he uot a Mr. of Leaden marmorca. 



1. G.cethalea, Ach. Syn. />■ l<». Unknown to me." — This last is stated bj 



Acharius to he found at Durham, by the Rev. Mr. U'iniiii.iii, it is thus 



characterized iu the Synopsis: "crusta determinate nigro-limitata 

 cinereo-fumosa tenuissime rimosa, apotheciis minutis mLins demum 

 planiusculis." If I understand the Acharian genus Gyalecta correctly, 

 it is distinguished from Urceolaria by the absenct of the border formed 



|»v the < -ri i - 1 to tlu- apothi i '• Mr- S< har.ir refers to it t! 



marmorea, Ach. : but Acharius 1 character would scarcely admit it. 



I.'.. LiE< Fl> \. . Ic/i. Le« idea. 



Timlin* cruataeeoua, spreading, adnaie, uniform. .1/ 

 (pakUtUd) orbicular, sessile, plano-convex, baring a fcordi 



