1 92 1. No. 7. STUDIES OX THE LICHEN" FLORA OF NORWAY. 1 79 



According to Zopf Paniuliu iwcresceiis (Arn.) contains the Salaza- 

 ninic acid, giving a red colour with KOH, but owing to the small quantity 

 the red colour should be faint. I could only find an intenseh" yellow or 

 vellowish-orange colour. Hle gives the same statement. ' 



The Norwegian specimens have but poorly developed isidia (less deve- 

 loped than in the specimens from Finistère), and must be referred to the 

 P. pilosclla of Hue. 



ParmcUa cxcrcsccus belongs to the section Aniplng\')iniia Wain., but 

 the naked marginal zone is narrow and occasionally the rhizines advance 

 to the margin. 



42. Parnielia trichotera Hue. 

 Map III, 2. 



\'ery rare: only recorded from Raegetjord, on our southwestern coast. 

 (Havaas Lieh. Exs. Xorv. 325, s. n. Parnielia perlata (L.) Ach. 



The positive KOH reaction of the medulla is very faint or even want- 

 ing. Wainio determined the specimens as ^Pannclia norvegica Wain., saltem 

 thallo margine lacinularum soredioso a Parui. nielaiiotlirica (Mont.) Wain. 

 difterens, at tantum sterilis visa.' 



17. Cetraria Ach. 



Thailus pseudocvphellis instructus. Subgen. Stigiuatophora Waix. 

 2. Medulla J caerulescens. 



3. Thallus planus vel concavus, non tubulosus i. C. is/andica. 

 3*. Thallus tubulosus, margines conniventes 2. C. crispa. 



2*. Medulla J non caerulescens 3. C. /liasce/is. 



Thallus pseudocvphellis destitutus. 



2. Thallus cylindricus vel depresso-C3-lindricus. Subgen. Coniiciilaria 



(Schreb. I. 

 3. Thallus indivisus vel parce furcatus 4. C. iioriiiörica 



3*. Thallus ramosissimus. 



4. Thallus pulvinatus, laciniae adscendentes, palmatim ramosae, 



subplanae 5. C. odontella 



4*. Thallus + caespitosus, laciniae erectae, + cylindricae 



6. C. toiiiissima. 

 2*. Thallus foliaceus vel foliaceo-fruticulosus. Subgen. Eucetraria (Kbr.). 

 3. Thallus albidus vel albido-cinerascens 7. C. diffusa. 



' Causerie p. p. 248 and 250. 



