94 
reaching elevations of from a little under 900 feet to 1,000 feet A. T. The 
ones south of Kirksville are the best preserved and appear to be remnants 
of the very old Tertiary peneplain or, perhaps, base level. It seems prob- 
able that the whole regicn covered by the map and the higher, rougher 
parts of southern Indiana are a part of the Lexington plain of Campbell, 
reaching from the Cumberlaiid Plateau westward to the Tennessee river, 
Fig. 13. A monadnock southwest of Bloomington. It rises 115 feet above the 
surrounding plain. It is surrounded by sinks, especially on the north, west and 
south. 
the Indiana portion being a spur extending northwest from the type region 
at Lexington. It will be noticed that the elevation of the old plain and 
monadnocks (catoctins) is materially lowered as the western ‘edge of the 
map is approached. This is due to the surface dip into the West Fork of 
White river basin. A similar beveling will be noted on approaching Salt 
creek in the southeast corner of the map, and Beanblossom in the north- 
eastern corner. Even in xn extremely old peneplain this bevelling toward 
the main stream of the basin is the normai condition and should be ex- 
pected to be found on a rejuvenated plain. 
