533, 
Andropogon furcatus 
Panicum virgatum 
Calamagrostis canadensis 
He Carex vesicaria 
Scirpus fluviatilis 
Fic. 1. Diagram showing the successions of the plant associations from 
swamp to prairie on the flood-plain of the Mississippi River at 
Savanna, Illinois. The dotted lines. represent local exceptions of 
rare occurrence. See Plates XLVIII-LIIT. 
The data obtained from the surveyors’ reports show that the greater 
amount of undisturbed flood-plain prairie occurs along the Mississippi 
River. Similar areas, however, occur along the Illinois and smaller 
rivers. The driest of these flood-plain prairies found, are along the 
Desplaines River near Riverside, in Cook county. These areas have been 
