CLEMENTS 



I 



,v.¥^ ^ 







A. Prisere alternes showing the serai stages from the bare diatom marsh to the lodgepole 

 subclimax, Firehole Basin, Yellowstone Park. 



B. Subsere alternes due to the removal of sods for adobe houses, showing three stages: 

 (1) rushes, (2) salt-grass, (3) Anemopsis, Albuquerque, New Mexico. 



