Plate III 



Above: Tundra plants, including a 40-yeai-old nearly prostrate willow. White Horse 

 Pass, Alaska. Photo by W. H. Camp. Below (left): The snow plant (Sarcodes) parasitic 

 on fvnigi in the pine forests of the Sierra Mountains, California. The plant develops soon 

 after the snow melts. Photo by W. H. Camp. Below (right): A Florida lichen, in which 

 the fungus is parasitic on purple bacteria. Photo by G. S. Crowl. 



