I9l6. No. 8. MONOGRAPH OF THE NORWEGIAN PHYSCIACEAE. 73 



KOERBER is of the opinion that the Lecanora virella* of ACHARIUS 

 Synopsis p. 191 is not our plant 1 , but he gives no arguments. The de- 

 scriptions of ACHARIUS quoted agree perfectly with our plant, and TH. 

 FRIES, who has seen the ACHARIAN herb., unhesitatingly accepts the 

 AGRARIAN name. 



I have never seen the combination " Physcia virella" used in literature. 

 It has been employed in the case of two exsiccates: MALME 158 (anno 

 1910), and MERESCHKOWSKY 71, 72 (anno 1913). 



Ex sic. ANZI Lich. Ital. sup. 126 (Farm, obscura var. virella] ANZI Lang. 

 293 (Farm, obscura var. orbicularis (NECK ) SCHAER.). ARNOLD Lich. Exs. 

 1368 (Ph. obscura var. virella). CLAUD, et HARM. Lich. Gall, praec. 180 

 (Ph. obscura var. ulothrix), 181 (Ph. obscura var. virella), 379 (Ph. obscura 

 var. cycloselis SCHAER., rhizinose receptacle). FLOERKE Deutsche Lichenen 

 94 (Farm, ulothrix ACH.). FRIES Lich. Suec. 205 (p. p. s. n. P. cycloselis). 

 HEPP Flecht. Eur. 55 (Lobaria obscura q leprosa, almost crustaceous speci- 

 men), 599 supr. inf. (Lob. obscura 17 virella). MALME Lich. Suec. 158. 

 MASSALONGO Lich. Ital. 247 (Squamaria obscura var. nigricans MASS.). 

 MERESCHKOWSKY Lich. Ross 71, 72. NORRL. et NYL. Herb. Lich. Fenn. 

 221 (Ph. ulothrix var. sorediosa NYL.), 222 (Ph. ulothrix (Acn.) NYL.). 

 RABENHORST Lich. Eur. 438 (Rinodina virella}. SCHAERER Lich. Helv. 355 

 (Farm, obscura e cycloselis SCHAER.), 607 sin. (Farm, obscura | virella 

 SCHAER.). 



Thallus orbicular, small, diam. 1 1,5 cm -> but inclined to grow in 

 dense clusters covering larger areas, especially on moist rocks ; on even 

 subtratum slightly appressed, sometimes almost crustaceous, on uneven more 

 or less spreading or subascendant. Laciniae very short (2 3 mm.), 

 initial laciniae stellate and contiguous, later they become imbricate; they are 

 plane or slightly convex, repeatedly deeply incise with crenate branches. 

 Longitudinal growth quickly checked by apical soredia, sometimes 

 spreading over the whole thallus. Soredia greyish-white, greyish green 

 or occasionally yellowish. Thallus withow isidia, opaque, grey or 

 greyish- green, greyish-brown or even dark brown, rarely greyish- 

 white, moistened distinctly green, lower side black, rarely pale or 

 even white at the circumference. Young laciniae with small stellate 

 white cilia at the margin. Rhizinae short, black, usually unbranched, 

 25 40 a thick. 



1 Parerga Lichenologica p. 72. 



