ACOTYLEDONS. LICHENS. Cctrar'ui. o7 



Hab. Trunks of old trees and pules, but not very common, Lightf. 



4. B. flavicans, thallus yfHow naked, segments dichotomously 

 branched slightly compressed attenuate divaricated compli- 

 cated, apothecia scattered tlieir disk plane orange red their 

 margin entire naked, ylcli. Syn. Licli.p. 225. Jjichen Jiavi- 

 cans, E, B. t. 2113. Lichen vulpinns^ Light/, p. 896. 



Hab. Trunks of old trees, but not common. On the ground on the 

 Craig of Ailsa, Lightf. 



\9. CKTRARIA, 

 Universal receptacle between cartilaginous and membranaceous, 

 ascending or spreading, lobed and laciniated, on each side 

 smootli and naked. Partial recept. scutolliform, obliquely 

 adnate with the margin of z'i\e thallus, the lower portion being 

 free (not united with the thallus), tlie upper sessile, the disk 

 coloured, phuio-concave, with a margin formed of the thallus 

 and inflexed. 



1. C. juniperina, tliailus pale yellow very yellow beneath, the 

 segments plane ascending erose crenate and crisped, aj)othecia 

 elevated their disk brown the margin crenulated. Jlch. Syn, 

 Lick. p. 226. 



/3. pi/iastri, thallus witli the segments de])resscd th.e lobes 

 rounded crenate the margins crisped pulverulent and very 

 yellow. Liche?! pi7iastri, E. £. t. 2[\l. Lichen ptniperinus. 

 Light/, p. 8o6. 



Hab. Trunks and branches of elms and many other trees, common. 

 Fir trees about Aviemore and at Kinnordy Kerrie-muir, Hook. 

 Never, I believe, found with apothecia in Britain ; though not rare 

 in that state in Switzerland. 



2. C. sepmcola, thallus olive-brown paler beneath the segments 

 plane ascending lobed waved subcrenate, apothecia elevated 

 of the same colour their margin rugose and crenulate. ylch. 

 Syji. Lich. p. 227. Lichen sepincola, E. B. t. 2386. 



Hab. On stones in the Scotch mountains, according to Mr. Dickson. 

 I have never seen it in any country but on wood. On fir trees at 

 Kinnordy Kerrie-muir, Mr. Lyell and Hook. Fruciijicution very rare. 



3. C. glauca, thallus glaucous somewhat shining sinuated and 

 lobed brown beneath, the segments cut and jagged <;urlcd 

 ascending, apothecia elevated chesnut brown their margin 

 wrinkled. Ach. Syn. Lich. p. 227. Lichen glaucns, LightJ, 

 p. 838. E.B.i. 1066. 



fS. /allaXy thallus white on each side, or with occasional black 



spots beneath. L. /allax, E. B. t. 2373. 

 Hab. On the ground in heathy places, on rocks and trees, not un- 



conunon. /S. On the ground near the cascade at Invcrary. 



4. C. nivalis, thallus sulphur-coloured orange at the base pitted 



