101 
angustis (latit. in nostra circa 0,5 millim.) et sepe soredia 
tuberculosa albida hinc inde proferentibus, multifidis, discrete 
divisis, convexiusculis, arcte adnatis (rhizinis non visibilibus); 
apothecia parva. 
Ad saxa gneissacea saltem ad Helsingfors (f. disereta Nyl. 1. c.). 
7. P. eentrifuga (L.) Ach., Nyl. Syn. p. 401. 
Thallus ochroleucus vel albido-flavescens adpressus centri- 
fagus (vel zonatim centrifugus), laciniis conferte contiguis vel 
subimbricatis, centro corrugatis, inequalibus, ambitu planiuscu- 
lis crenatis vel crenato-incisis, subtus albidus (rhizinis sordidis); 
apothecia spadicea vel spadiceo-rufa (presertim situ centra- 
lia) mediocria. 
Ad rupes granitosas in terris Scandinavicis frequentissime. 
3. P. incurva (Pers.) Fr., Nyl. Syn. p. 402. 
Thallus ochroleucus vel albide flavo-cinerascens subopacus 
orbicularis stellato-laciniosus mediocris (sepius adpressus), la- 
ciniis angustis multifidis convexiusculis confertis apicibus (ple- 
rumque) incurvis nonnihilque imbricatis, soredia albo-flavescen- 
tia hinc inde proferens verrucoso-tuberculosa majuscula, subtus 
concolor (at fuleris rhizineis nigricantibus sepius tectus); apo- 
thecia Spadiceo-fusca vel obscure rufescentia parva vel me- 
dioeria. 
| Ad saxa granitosa in Scandinavia passim sat frequens, usque 
in Lapponia.  Raro fertilis. 
9. P. acetabulum (Neck.) Dub., Nyl. Syn. p. 402; Par- 
melia corrugata Ach. 
Thallus glauco-olivaceus vel olivaceo-luridus (vel passim 
Pallidius luridus) subopacus orbicularis (majusculus) inequalis 
vel rugulosus lobatus, lobis flexuosis vel imbricatis, subtus ca- 
staneo-fuscus vel nigricans (aut pallescens); apothecia badio- 
rufa mediocria vel magna (sepe latit. semipollicaris). 
Ad truncos arborum usque in Sueciam mediam rarius. 
10. P. olivacea (L.) Ach., Nyl. Syn. p. 403. 
SThallus olivaceo-fuscus vel badius vel badio-umbrinus orbi- 
Cularis vel suborbicularis rugosulus vel crebre minute corruga- 
