148 



PLANT SOCIOLOGY 



Wind pressure causes injury by crippling and deforming trees and 

 shrubs. Injury to young shoots and buds on the windward side is 



1' lu. o-±. — HiueuL oi biiow uiaau ou tjApoiseu iiugea lu lati m^n jn.Lij, 



Silene acaulis cut away on one side. Flimerstein, 2,670 m., January, 1911. 2. Elyna 

 myosuroidcs partially eroded. Aelpli Pass, 2,640 m. 3. Androsace helvetica cushion 

 killed on one side. Stazerhorn, snowless rock promontory, 2,500 m. 4. Elyna myo- 

 suroides from Piz Lagalb, 2,600 m. 5. Fcduca glacialis cushion cut away on one side. 

 Pyrenees, 2,660 m. {Braxm-Blanquet.) 



often accompanied by increasing growth on the leeward side, forming 

 those peculiar flag shapes and trimmed-up, smooth-shorn hedge forms 



