An Indiana beech is without doubt one of the most sensitive indicators of decline in mesphytism in habitat. In the rugged areas of the state it marks the borders between moist northfacing slopes and more xeric south-facing slopes. This was shown by Potzger, Potzger and Friesner for the southern as well as for the eastern part of Indiana. Beech also records the effects which the increase of steepness of slope has on the usual more mesic conditions of north-facing slopes. This characteristic of the species suggested a study of the forests along the eastern periphery of our Indiana prairie area to see if the transition between mesophytic forest and prairie functioned as a progressive change or represented a sudden break between two vegetation types. The senior author is engaged in a study of the original vegetation of the state, using as basis the witness trees noted and recorded by the men who made the original U. S. land survey. The study of distribution of beech along the border of the prairie peninsula is one of several papers dealing with phases of the state-wide survey which seem to warrant more detailed consideration.