42 ACOTYLEDONS.^ LICHENS. Opegi'cijiha. 



Hab. Highland mountains, on rocks near their summits, conimon, 

 • The G. arctica, E. B. t. 2485, is but a var. of this. 



3. G. cyUndrica, thallus somewhat naked dark greenish grey 

 folded and lobed strongly ciliated beneath smooth pale with 

 branching fibres, apothecia elevated nearly plane with con- 

 centric and plaited lines. Ach. Syn. Lick. p. 65. Liche?i 

 crivitus, Liglilf. p. 522. L'iche?i prohoscideus, E. B. t. 522. 



Hab. Rocks on the Highland mountains, not uncommon. 



4. G. erosa, thallus rugged olivaceous brown its circumference 

 perforated and laciniated dark grey beneath glabrous somewhat 

 granulated and fibrous, a];othecia somewhat convex variously 

 ])laited. Jlch. Syn. IJch.p. 65. E. B. t. 20G6. Lichen tor- 

 refactus, Ligklf. p. 862. 



Hab. Rocks on the Highland moimtains, frequent, especially near the 

 summits. 



5. G. dcusta, thallus roushish olivaceous brown with a brown 

 scattered dust smooth beneath wiih pits and reticulations na- 

 ked of the same colour, apothecia plane with circular })laits at 

 length convex. Ach. Sy?i. Lick. p. 66. E. B. t. 24S3. 



Hab. Rocks in the Highlands of Scotland^ Dickson, Mr. Turner and 

 Hook. 



6. G. piishtlala, thallus blistered and vvartv greenish ash-colour 

 beneath deeply pitted smooth palish brown naked, apothecia 

 few plane margined, disk somewhat even papillose and plaited. 

 Ack. Syn. Lick. p. 66. Licken pust.j E. B. t. 1283. Lighlf. 

 p. 858. 



Hab. Rocks on the Highland mountains, not unfrequent. Light/. 

 The fruit is rare, and has been found by Mr. Menzies ; and by Mr. 

 Borrer and myself on rocks in Skye. 



7. G. pellita, thallus smooth sinuato-lobate of a greenish coppery 

 brown beneath black with dense pulvinate fibres, apothecia 

 sessile at length somewhat globose variously plaited intricate, 

 Ach. Syn. Lick. p. 67. Lichen pellitns, E. B. ^.931. L. po- 

 lyrhizns, LighlJ\ p. 864. 



Hab. Rocks on the Highland mountains, fi'equent. 



7. OPEGRAPHA. 

 'Universal receptacle crustaceous, spreading, plane, adnate, uni- 

 form. Partial recept. oblong, elongated, sessile, covered with 

 a cartilaginous black membrane, its disk linear, margined on 

 each side. 



1. O. Persoonii, crust tartareous snioothish cohering uneven 

 whitish, apothecia innate oblong their disk resembling a cleft, 

 at length rugose waved plaited dissimilar rather confluent with 

 the disk irregular somewhat dehiscent. Ach. Syn. Lick. p. 71. 



^. aporea, crust tartareous or leprose uneven pulverulent, apo- 

 thecia roundish dissimilar waved ))laited tortuose and variously 

 expanded in the disk. Lichen simplex^ L. B, t, 2152, 



