1916. No. 8. MONOGRAPH OF THE NORWEGIAN PHYSCIACEAE. 59 



has a black lower side and narrow elongate laciniae, and cannot be 

 referred to f. lenta. 



The whole thallus covered with a white or greyish-white 

 pruina; when moistened, the thallus is more or less dark greyish-green. 

 Lower side white, in the central part only more or less dark. Rhi- 

 zinae scattered, pale or finally dark. Laciniae at first slightly appressed, 

 but during the growth they become more or less ascendent. They are 

 broad and short, deeply incise with rounded ends, the ascendent ones 

 slightly crisp at the margins. 



This variety is not frequent in Norway. I have only seen it from 

 Northern Norway: Saltdalen (hb. SOMFT.), and Tromseen (hb. BLYTT). The 

 specimens were sterile. 



f. squarrosa (Acn.) 



Parmetia muscigena y squarrosa ACHARIUS Lich. Univ. (1810) p. 473. 



Physcia pulverulenta var. squarrosa ACH. TH. FRIES Lich. Scand. I 

 (1871) p. 138. 



Ex sic. ARNOLD 64 b. KOERBER Lich. sel. Germ. 102. (Anaptychia 

 ciliaris y hurnilis KBR.). 



Differs from the type in having erect, more or less closely im- 

 bricate to panniform laciniae, which are eaqually broad or at their 

 ends dilated and crenate. Pruina is found from the ends of the laciniae 

 in various extensions towards the centre. Colour greyish or bluish-violet 

 to greyish-white or white, lower side at least at the ends of the 

 laciniae pale, but it becomes darker towards the central part. 



Apothecia as in the type. 



f. squarrosa is hardly a noteworthy form, connected with the type 

 by numerous intermediate states. It is especially found in Northern Nor- 

 way. Finmarken: Honningsvaag (HAVAAS) and Skoganvarre (LYNGE), 

 Tromse amt: Skibotn, Lyngseidet, Tromseen, Nordbynesset, and Rosta- 

 vand (LYNGE). 



In our copy of KOERBER'S exsiccate No. 102 is different from TH. FRIES'S 

 specimens of Ph. pulverulenta d tenuis (KBR.); these belong to Ph. constipata, 

 here treated as a proper species. 



