190 L1CHENES. [Lecanora. 



19. L. rubra, Ach. {red-shielded Elm Lecanora)', crust 

 leprous white thin uneven continuous, apotliecia numerous 

 sessile concave brownish-salmon-colour (or red) with a thick 

 elevated powdery crenate inflexed border. Sm. — Ach. Syn. 

 p. 177 Lichen Ulmi, Sw.—E. Bot. t. 2218. 



On the bark of old Elms, Yorkshire, Mr. Borrer. 



20. L. H&matomma, Ach. (blood- specked Lecanora); crust 

 leproso-tartareous pulverulent white or pale sulphur-coloured 

 with a fibrous border, apotliecia imbedded scarlet concave, when 

 old convex, the border thick white elevated remarkably inflexed 

 mealy at length spreading.— Ach. Syn. p. 170.— Lichen Hcema- 

 tomma, Ehrh. — E. Bot. t. 486 — Lichen coccineus, Dicks. Cr. 

 Fasc. 1. p. 8. t. 2. /. 1. E. Bot t. 223. — Lecanora Stonei, 

 Ach. Syn. p. 170. 



Rocks and brick-walls, in various places. On Stonehenge, Wiltshire. 

 Salisbury Craigs, Edinburgh. On the large Cross at Iona.— The Lichen 

 coccineus of E. Bot. appears to be only an old state of the L. Hcema- 

 tomma. 



21. L. cerina, Ach. (waxy Lecanora); crust somewhat granu- 

 lated greyish-white, apotliecia scattered elevated flat at length 

 convex yellow waxy, the border inflexed somewhat pruinose. — 

 Ach. Syn. p. 173. — Lichen cerinus, Dicks, Cr. Fasc. 3. p. 14. 

 E. Bot. t. 627. 



Trunks of trees, Norfolk and near London. 



22. L. crenuldta, (little crenated Lecanora); crust scattered 

 ash-coloured very thin, apotliecia minute dispersed brownish- 

 grey with an elevated crenated whitish margin. Sm. — Lichen 

 crenulatus, Dicks. Cr. Fasc. 3. p. 14. t. 9.f. 1 — Lichen dispersus, 

 Ach. Prodr. (Sm.)— Lecanora galactina, /3. Ach. Syn. p. 187. 



Limestone rocks, South of England. 



23. L. byssi?ia, (mealy-bordered Lecanora); crust powdery 

 brownish, apotliecia flat dull yellow with a very white mealy 

 elevated border (when old double). Sm — Lichen byssinus, 

 Dicks. Cr. Fasc. 2. p. 19. E. Bot. t. 432. 



On trees and stones, Scotland, Mr. Dickson. On brick, near London, 

 5 m ._Thi s and the preceding are, to me, very obscure plants. Acharius 

 seems inclined to refer the present to L. cerina, but the figure is very 

 unlike that species. 



24. L. chloroleuca, Ach. (green and white Lecanora); crust 

 white leprous very thin, apothecia crowded elevated flat olive- 

 green the border white undulated. Sm — Ach. Syn. p. 160. 

 — Lichen chloroleucus, E. Bot. t. 1373. 



On mosses, in alpine countries. 



25. L. vdria, Ach. (variable-shielded Lecanora); crust thin 

 granulated scattered pale yellowish-green, apotliecia crowded 

 flattish buff or brown the border waved irregular inflexed. 

 Sm. — Ach. Syn. p. 161. — Lichen varius, Ach. Prodr. — Dicks. 

 E. Bot. t. 1666. 



On old posts and pales. On rocks, Appin, Capt. Carmichael. 



