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across. The color is dull, grayish brown, with a pale under surface 

 difficult to see. 



Fruits usually present, up to 2 mm. in diameter, but usually 

 smaller, blackish, with a thin, brown rim, somewhat notched. 

 Spores 2-celled, brown, 13 to 22 by 7 to 10 microns. 



Physcia adglutiiiata is more likely to be mistaken for one of 

 the Crust Lichens than for any other Papery Lichen, but some 

 trace of the papery lobing is always present to distinguish it from 

 Rinodina sophodes (Group 20), which has similar spores. In well 

 developed forms, the thinness of the tightly clinging tips separates 

 it from all other species of Physcia. P. stellaris has usually a central 

 crust, but its much thicker tips are pale gray, not brown. P. obscura 

 and P. endochrysea have a dull drab shade, but their tips are loosely 

 attached to the bark by many black holdfasts. Parmelia olivacea and 

 its subspecies (Group 5) have brown, close-clinging lobes, and an 

 often crust-like center, but their upper surface looks almost metallic, 

 usually shining like bronze, while that of the Physcia is dull and 

 delicate. 



{Group 8 to he continued in Part 8) 



RiDGEWOOD, N. J. 



