PROCEEDINGS 



OF THK 



CALIFORNIA x\CADEMY OF SCIENCES. 



Third Series. 



Botany. Vol. I, No. 7. 



The Nature of the Association of Alga 

 and Fungus in Lichens. 



BY 



George James Peirce, 



Assistant Professor of Plant-Physiology, Leland Stanford J iinior University. 



With One Plate. 



Issued June 5, 1899 



SAN FRANCISCO: 



Published by the Academy. 



1S99. 



