Plate XI. 



-ie' 





-■V 



- V, 





Fig-. 1. Development of the Stenophylltis association in a shallow blowout in the Hanover 

 area. The conspicuous erect plants are Oenothera rhombipetala. 



Fig-. 2. Blowout in the Oquawka area. Stabilization is besfinning-, as shown b\- the persist- 

 ence of the grasses at the base of the windward slope, the conspicuous plants of Lcspedcza cap- 

 liaia, patches of moss, and by the thicket of Populus dcltoides in the background, at the left. 



