IQI6. No. 8. MONOGRAPH OF THE NORWEGIAN PHYSCIACEAE. 47 



nate mass of sorediate, panniform, 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 thick, at the exterior part (13 25 /<) greyish, 

 opaque, with very indistinct hyphae, otherwise uncoloured with distinct 

 hyphae. Hyphae plectenchymatous, more or less perpendicular to 

 the surface, especially at the exterior part, very constrictedly septate, thin 

 (3 5 ( ) 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 very 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 wh ; ch 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 80 105/4 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) a thick, 

 with a tinge of grey at the surface, otherwise uncoloured. The plecten- 

 chymatous 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. Hypothecium uncoloured, thick: 

 50 60 //. Disc plane, white, very pruinose. Hymenium covered 

 with an uncoloured, amorphous, broken stratum, occasionally containing 

 crystals of oxalate of lime (CaC 2 O 4 ); hymenium 80 100 f.i thick, at the 

 exterior part (16 25^) dark 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^ long, 15 20 ( u thick, well developed, octosporous. 

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



