THE ECOLOGY OF SAND Dl'NE PLANTS 



207 



Fia. ] 



Fig. 2 



Fig. 1. General view of dunes near Redondo, C'aliiornia. showing hummocks 

 and the enci'oachment of sand on new territory. 



Fig. 2. Ripple-marked sand, with Gnertncrui in center and distance. 



Fig. 3 



Fig. 4 



Fig. 3. Abronia, in a characteristic situation, together with Eriogonum, Cheir- 

 anthiiK and Eremocarpus. 



Fig. 4. Cheiranthu^ in a characteristic location, and of typical form. 



