1916. No. 8. MONOGRAPH OF THE NORWEGIAN FHYSCIACEAE. 39 



Reaction: Cortex slightly yellow by KOH, medulla uncoloured, 

 no colouring by CaCl 2 O 2 . Hymenium persistently blue or bluish-black by J. 



Hab. On the bark of deciduous trees, espe- 

 cially in avenues and trees in open situations, 

 very rarely on rocks (moist Atlantic climate in 

 Western Norway). It has a great predilection for p . ph gda 



the thin twigs of Prunus spinosa, wild Rides ascendens Bitter. 



rubrum and the like along the coast. 



Loc. Physcia ascendens belongs to the southern lowlands and is not 

 recorded north of Trondhjem. It is frequent about Kristiania: Teien, 

 Hovedeen, Ekeberg (MoE), Hevik, Blommenholm (KI^ER), Skogumsaasen 

 (LYNGE), also in the south-eastern lowlands: Nitedal (MoE), Heland (LYNGE), 

 Sundvolden (HAVAAS and LYNGE), Minne, Hersjeen, Brandbu (LYNGE), 

 Veldre (NORDHAGEN). Not (yet) recorded from our great south-eastern 

 valleys. Frequent along the south and west coast: Haaeen (BLYTT), Hvaler 

 (LYNGE), Larvik (BLYTT), Moster (HAVAAS and LYNGE, at Moster also 

 saxicolous), less frequent towards the inland end of the western fjords 

 (HAVAAS in lit.); Voss (HAVAAS). Trondhjem: Ladehammern (KINDT). Not 

 recorded north of Trondhjem. 



4. Physcia tenella, (Scop.) emend. BITTER. 



Lichen tenellus SCOPOLI Flora Carniolica ed. 2 a (1772) p. 394. 

 Physcia tenella BITTER Ueber die Variabilitat einiger Laubflechten 

 (1901) p. 431 et 432 fig. 2. 



The synonymy of this species is very intricate and the priority cannot be 

 decided without a study of the authentic specimens of early authors. I 

 have not seen the Physcia tenella of SCOPOLI. In naming the species 

 BITTER does not argue from a point of priority, but from morphological 

 views (Durch die genannten Eigenschaften ist der Artname der beiden 

 Lichenen begriindet*). A full list of uncertain synonyms will make bad 

 worse. 



Exsic. CLAUD, et HARM. Lich. Gall, praecip. 128, FLOERKE Deutsche 

 Lich. 73, FLOTOW Lich. Exsic. 90 B and 90 Bb (at least in our herb., s. n. 

 Parmelia stellaris fornicata WALLR.), HAVAAS Lich. Norv. 336 (near Ph. 

 leptalea], NORRL. et NYL. Herb. Lich. Fenn. 216 (Physcia stellaris * tenella 

 f. subbreviata NYL. in lit.), RCHB. et SCHUB. 37, STENHAMMAR Lich. Suec. 

 212 inf. (Parmelia caesia). 



