288 Rev. W. A. Leiirhton on the British Umbilicaria\ 



plant of Dillenius, 545. t. 82. f. 5, '' on rocks near Settle in York- 

 shire." 



** Thallus ashy-grey when dry. 



7). grisea, Hoffni. Thallus thin, crenate, somewhat lobed, 

 j)apillose on both sides ; upper side pale ash-coloured, naked ; 

 under mostly naked, blackish. 



Lichen puhnonarius saxatilis, e cinereo-fuscus, minimus, Tourn. Instit. 5Jf) 



(1/19); Vaill. Paris. 116. t. 21. f. 14. 

 Lichenoides saxatile, foliis minus divisis, cinereo-fuscum, Dill, in Raii Svu. 



73(1/24). 



coriaceum cinereum, peltis a*ns compressis, Dill. 219. 



Lichen deustus, Robs. Br. Fl. ;30() (1777) t. 30. f. 11/ (1741) (fide lierbarii 



Dilleniani cl. Borrero teste). 

 griseus, Swartz in N. Act. Stockli. v. p . 91 . t. 2. f. 3 (fide Aeh.) ; Westr. 



in Act. Stockh. 1793 (fide Ach.J; Retz. Scand. 28(5. 

 Umbilicaria grisea, Hoffm. Fl. Germ. 2. Ill (1795). 

 Lichen Dillenii, With. Arr. 4. 63 (1796). 



murinus, Ach. Prodr. 143 (1798). 



Umbilicaria murina,'DC. Fl. Fran?. 3rd ed. 3. 412 (1805); Nyl. N. Class. 



176. 

 Gyrophora hirsuta, y. murina, Florke in Berlin Mag. 1810, p. 67 (fide 



Schserer). 

 Gyrophora murina, Ach. Meth. 110 (1803); L. Univ. 231 ; Syn. 69; Sm. 



E. Bot. t. 2486 ; Stenh. in Sched. Crit. fasc. 5 & 6. no. 132 (1825) ; 



Hook. Brit. Fl. 2. 218 ; Chev. Paris. 1. 643. t. 14. f. 11 c. 



grisea. Turn. & Borr. Lieh. Brit. 236 (1813). 



Umbilicaria depressa, /3. spadochroa A, Schar. Spicil. 82. 362 (1823-36). 

 Gyromium velleum, 8. murinvm, Wahl. Fl. Suec. 857 (1824-26). 

 Graphis vellea, /3. alutacea, Wallr. Crypt. Germ. 344 (1831). 

 Umbilicaria vellea, y. hirsuta, * murina, Fries, L. Reform. 358 (1831); 



Summa Veg. Scand. 117- 

 vellea, y. spadochroa, a. grisea, Scha^r. Eniim. 24 (1850). 



Found on St. Vincent^s Hocks near Bristol by Mr. Dare, Bil- 

 lenius. 



" Thallus peltate, consisting generally of a single, orbicular, 

 crumpled, concave leaf, from an inch to an inch and a half in dia- 

 meter ; sometimes of two or three smaller leaves ; attached to the 

 stone on which it grows by a callous central dii^k, divided at the 

 edges into a few, shallow, rounded lobes, and irregularly notched 

 or crenatc : upper surface of an ash-colour, with a slight tinge 

 of brownish-green when wet ; wdiite ash-colour and subpruinose, 

 but still brownish towards the edges, when dry ; granulated, as 

 if minutely cracked all over, but smooth to the touch, and 

 scarcely appearing rough to the naked eye : under surface, 

 whether wet or dry, dark brown, varying to almost black, 

 covered with a minute shagreen-like roughness, naked, or very 

 rarely producing a few scattered branched fibres : substance thin, 

 flexible when wet, and still somewhat flexible, but brittle, when 



