94 



reacliiug- elevations of from a little uudev 0(30 feet to 1,000 feet A. T. The 

 ones sonth of Kirksville ai'e the best preserved and appear to be remnants 

 of the very old Tertiary peneplain or, perhaps, base level. It seems prob- 

 able that th.e whole region coA'ered by the map and tlie higher, rougher 

 parts of southern Indiana are a part of the Lexington plain of Campbell, 

 reaching from the Cumberland Plateau westward to the Tennessee river. 



_ ^fe ■ . I'B^^r: " 



Fig. i:;. A uionaduock southwest of Bloomingtou. It rises 115 feet above tlio 

 suri-onnding plain. It is siu-rouncled bj- sinks, especially on the north, west and 

 soutli. 



the Indiana portion being a spur extending northwest from the tj'pe 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 tlie map, and Beanblossom m the north- 

 eastern corner. Even in an extremely old pcnejdain this bevelling toward 

 the main stream of the basin is the normai condition and should be ex- 

 pected to be found mi a re.in^■enated plain. 



