Gyrophora.] LICHENES. 217 



plish-brown besprinkled with superficial or marginal dark 

 powdery warts, apothecia red-brown broader than long on short 



proper lobules. — Ach. Syn. p. 242 Lichen parilis, Ach. Prodr. 



—E. Bot. t. 2360. 



In an old stone-quarry, in Shropshire, Rev. E. WiUiavu, (E. Bot.). — 

 I am not aware that any British Botanist has met with this Lichen, ex- 

 cept Mr. Williams : nor was he so fortunate as to detect its fructification, 

 which Acharius describes from Swedish specimens. Sir J. E. Smith 

 found it in Switzerland, but always barren. 



b. Attachment of the more or less orbicular thallus by the centre. 



Fam. XII. Umbilicarie.e. 



24. Gyrophora. Ach. Gyrophora. 



Thallus foliaceous, coriaceous or membranaceous, fixed by the 

 centre, peltate. Apothecia (trices or gyromata) orbicular, sub- 

 scutelliform, sessile and adnate, covered by a black membrane, 

 the dish marked with concentric circles or plicce, with a border or' 

 its own substance. — Name; yvsog, a circle and pogog, fertile, from 

 the peculiar nature of the apothecia. — Various species of this 

 Genus (and they are found in cold rocky situations, especially 

 on granite, in almost all parts of the world) constitute the Tripe 

 de roche of the Canadians and with G. proboscidea, G. vellea, 

 and a few other American ones, Capt. Sir J. Franklin and his 

 brave companions were supported in Arctic America, during a 

 season of want such as, happily, few human beings have been 

 subjected to. They are, however, bitter and nauseous, and can 

 only be employed in the total absence of every other salutary 

 food. 



1. Gr, polyphijUa. {many-leaved Gyrophora'); thallus naked and 

 smooth on both sides dark olive-brown shining above dull-black 

 beneath variously lobed &1 the margin simple or many-leaved, 



apothecia convex rough and plaited. — Lichen polyphyllue, Linn. 

 — /,'. Hot.t. L282. — I mbilicaria polyphylla, Schrad — Hoffm, PL 

 Lich. t. 59. f. '2. — Gyrophora glabra^ Ach. Syrup* b ,; k — Lichen 

 glaber, Ach* Met It. — Umbilicaria tenea, y.. Schorr. Lnh. Ihlc. 

 Spicil.p. 90. Lid,. Exsicc. n. 149,— Dili Muse. t. 30./ 129* 

 Hocks in mountainous countries, frequent. 



2. (J. proboscidea, Ach* (Proboscis Gyrophora); thallus sim- 

 ple membranaceous rugose with elevated reticulations of ■ 

 smoky-brown colour lobed and erose at tin- margin beneath 



BubfibriUose and paler, apothecia rather convex variously plait- 

 ed. — Ach. Syn, />. 64. /■/. Bot, t. 2484. — Lichen prehotcideu*\\ 

 Ach. Prodr, p, 1 17.— L,deuaiue% Lii/htf. — Umbilicaria poiymor- 



jiha. -J. Stlm r. Lich. Ilch\ Spied. />. 88, Lich. ExsicC. n. 148. — 



I mbilioaria congesta, Hoffm, LI. Lich. t. \.\. f. 4 — ".- -■■. arctica; 

 thicker and more rigid, more obtusely corrugated and sprinkled 



