507 
MORAINE RIDGES. 
(Map.) 
To one accustomed to a hilly or mountainous country only, these 
elevations would seem too insignificant for consideration either as 
features of the topography or as factors in the distribution of animal 
life. They seldom stand more than eighty feet above the plains, and 
their rise is usually distributed over a mile in extent. But to 
those long accustomed to a prairie region they are striking objects, 
and even have something of quiet grandeur. Except in the vicinity 
of rivers, these moraines were destitute of trees, and were 
classed, with the till plains, as prairie by early settlers. The species 
of plants and animals found on these ridges are largely the same as 
those found on the plains, and the difference between the fauna 
and flora of the two is due chiefly to the relative abundance of the 
species in the two regions. The peculiarities of the moraines are 
due to better drainage, to the results of erosion, and to the greater 
‘exposure to the wind. In consequence of the better drainage 
aquatic forms are absent except in sags or 1n depressions. Because 
of erosion and leaching the black soil on the ridges is less deep and 
perhaps less fertile than that of the plains, and, consequently, under 
original conditions the vegetation was less luxuriant on the moraines. 
The exposure to wind, which perhaps so far as mammals are con- 
cerned is a negligible factor during the summer, becomes a very im- 
portant one during the winter. 
The conditions of cultivation on the ridges are practically the 
same as those on the plains. 
These ridges are the favorite habitat of the striped gopher. 
Wherever the surface of the ground has been undisturbed long 
enough for these gophers to dare to dig their burrows one will be 
sure to hear their plaintive, questioning whistle on any bright sum- 
mer day. Moles also are more abundant on the slopes of the 
moraines than anywhere else in the county. Under certain con- 
ditions the white-footed prairie-mouse is also abundant. These 
three species are often found together, and certain spots containing 
a few acres inhabited by them have the densest mammalian life 
that I have seen in the county. Their burrows are so close together 
and all three animals are so abundant, that I believe they do not 
interfere with each other in any way. 
