340 T//e American (rCit/or/isL December, 189» 
casion:illy a single mound 80 or 100 feet above the lower 
plains, with an area of i)robably half an acre on the suniniit. 
Other nioniids may be near, or distant two, five, or fifteen 
miles. The visibly depressed or eroded area may be a ]tris- 
moid 100 feet deep by five or ten miles in one direction and 
twenty miles or more in another."* 
On the main watershed I find generally very long, sometimes 
narrow, and again broad ridges, which merge into the broad 
plain-like country of the crest or, as it has been called, plateau 
portion of the Ozarks. Also from Scholten in Barry county, 
extending several miles toward the northwest, there is a nar- 
row ridge, com])()sed of Carboniferous sandstone and conglom- 
erate, rising from 25 to 50 feet above the surrounding upland 
country. This is entirely isolated, being distant about ten 
miles from the plateau country near Aurora. 
The mounds and short ridges here discussed maybe specifi- 
cally classed with the monadnocks of New P^ngland; and 
they may be said to bear the same relation to the surrounding- 
peneplain as do the "mounds'" of the lead region of Wisconsin, 
Iowa, and Illinois. Although much less conspicuous features 
of the topography, their existence is e(iually significant with 
the other members of the class named. 
There is another series of elevations on the surface of the 
Jura-Cretaceous peneplain. For examples of these I shall 
draw chiefly from the counties of Barry and Stone, in the 
southwestern part of Missouri. The upland country here is 
composed of the hard chei-ty limestones of the Kinderhook and 
Burlington formations, which have resisted erosion better 
than the magnesian limestones to the east, and hence better 
preserve the original outlines of the peneplain. It has already 
been remarked that the hill-tops in the Burlington limestone 
areas rise to a nearly uniform bight. But close observation 
shows that the ancient plain thus represented is not now level, 
but rises very gently from the vicinity of the streams to the 
watersheds. The rate generally does not exceed a few feet 
per mile, and the exceedingly shallow basins thus formed are 
nearly imperceptible. Occasionally several streams head in 
some slightly undulating elevated tract of small extent, and 
flow outward to all points of the compass. Such a tract occurs 
* American Geolo<;ist, vol. xiv, p. 388, Dec, 1894. 
