igi6. No. 8. MONOGRAPH OF THE NORWEGIAN PHYSCIACEAE. 47 



nate mass of sorediate, pannifojin, short, broad scales. Thallus very fragile. 

 Laciniae more or less convex, of a chalky lustre, without or rarely 

 with few and scattered marginal cilia, minutely rugulose and albomaculate, 

 colour white or whitish-grey, moistened almost unaltered (only a 

 faint tinge of green at the soredia and more distinct white spots). Lower 

 side uncoloured or pale whitish-grey with few, scattered rhizines of the same 

 or a somewhat darker colour. 



Thallus covered with a very irregular amorphous, uncoloured stratum, 

 in places breaking up to an insperse mass. Upper cortex from o (sore- 

 dia) to 40 — 50 or even 140 m thick, at the exterior part (13 — 25 /1) greyish, 

 opaque, with verj- indistinct hyphae, otherwise uncoloured with distinct 

 hvphae. Hyphae plectench y matous, more or less perpendicular to 

 the surtace. especially at the exterior part, ver}' constrictedh' septate, thin 

 (3 — 5 u) and thin-walled. Gonidia disposed in large, incontinuous glome- 

 ruli, under and in the upper cortex, also in places where soredia are not 

 formed; the distance from the outermost soredia to the surface is accor- 

 dingly ver^' variable. In appressed laciniae the gonidia are only found 

 within the upper cortex (normal position), in ascendant ones quite as much 

 within either cortex. Medulla white, gradually transformed into the lower 

 cortex whch has thicker and more densely interlaced hyphae than the 

 medulla. They are not plectenchymatous, their direction is inde- 

 terminate, the majority- of them more or less parallel to the surface. Rhi- 

 zinae 80 — 105« thick. 



Apothecia very- rare, at least in this country. If developed they are 

 crowded, orbicular or angular, i — 1.5, rarely 2 mm. in diameter. Margin 

 entire or crenate. Receptacle (and margin) frequently sorediate, it is 

 without rhizinae, uniformly coloured (pale); cortex o — 100 ( — 140)« thick, 

 with a tinge of grey at the surl'ace, otherwise uncoloured. The plecten- 

 ch^-matous structure less developed than in the upper thalline cortex, hy- 

 phae perpendicular to the surface, rather thick- walled, constrictedly septate. 

 Gonidia crowded in the margin and within the whole cortex, also though 

 less numerous under the hypothecium. Hv-pothecium uncoloured, thick: 

 50 — 60 u. Disc plane, white, very pruinose. Hymenium covered 

 with an uncoloured, amorphous, broken stratum, occasionally containing 

 crj'stals of oxalate of lime (CaQOi); hymenium 80 — 100 li thick, at the 

 exterior part (16—2511) ^^^^ brownish-red, otherwise uncoloured. Para- 

 physes at their apices capitato — or clavato — incrassate and distinctly 

 constrictedly septate, unbranched or furcate, or with a few short lateral 

 branches. Asci 60 — 75 m long, 15 — 20« thick, well developed, octosporous. 

 Spores (in all the apothecia examined) poorly developed, either entirely 



