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OHIO BIOLOGICAL SUEVEY 



The Caves. Altho not, strictly speaking, always rocky habitats, 

 the flora of the caves is clearly most nearly allied to that of the rocks. 

 Altho they have some elements in common, the moisture content of 

 these habitats separates them sharply into two classes. 



Dry Caves. Old Man's Cave (fig. 23) is the dryest of the large 

 caves. Its roof overhangs sufficiently to protect it from all rainfall. 



Fig. 23. Old Man's Cave. Aralia spinosa in Foreground. 

 The ladder gives the scale. 



