SHREVE 



Plate 2 



A. South face of Santa Catalina Mountains viewed 7 miles from their base. Mount Lcmmon is on right center. 

 In foreground is bajada vegetation of Covillea tridentata, Opuntia spinosior, and Isocoma hartwegi. 





B. Extreme southwestern ridge of Santa Catalinas viewed from the north. In foreground is the bed of the Canada 

 del Oro, with individuals of Hymenoclea monogyra and a marginal fringe of Prosopis velutina and Chil- 

 opsis linearis. 



