Results Observed September 1978 
Stela A 
Lower quadrats; 
N- E, and W sides: clean (originally no lichen cover) 
ge 
S side: Dirinaria gone, Leptotrema now mostly gone, white crust , 
shadow left: background algal cover much attenatuated, 
Mid quadrats; 
E, W sides; already clean 
N side: Phyllopsora 50% or Byt-< gone, crumbles easily, 
S side: Most eyo peers cones remnants of algae left, 
Upper suadrete: 
N side: Phyllopsora virtually all gone 
EK side: Blga and Phyllopsora mostly gone now; orange crust perists 
S side: Alga 80% gone; Dirinaria already gone; Lepraria 10% left 
W side: clean 
