Widmann — A Preliminary Catalog of the Birds of Missouri. 11 



but a few days, giving way to the bright sunshine and strong 

 winds following in their wake. 



VI. TOPOGRAPHY. 



Missouri has three topographic divisions: the prairie region 

 in the north and central west, the Ozark region in the south, and 

 the lowlands in the southeast. There is a sharp line sepa- 

 rating the lowlands from the Ozarks, but the dividing line be- 

 tween the other two regions is indistinct, following in the main 

 the Missouri River westward to Boonville, there turning south- 

 westward through Clinton, Appleton City, and Nevada to La- 

 mar, leaving the state where the Spring River crosses the 

 line. 



The Ozark region has its highest elevation in a plateau, a broad, 

 comparatively even, stretch of high land, which reaches from 

 Perry, Ste. Genevieve, and Jefferson Counties southwestward 

 to the southwest corner of the state. It attains a height of 1100' 

 in St. Francois Co., IGOO' in Iron and Reynolds Cos., 1400' in 

 Dent, 1700' in Wright and 1550' in Stone, Barry and Taney 

 Counties. This upland is not a contiguous stretch, but is inter- 

 rupted by shallow, rather wide troughs and by broad areas 

 where the water disappears and runs in underground channels; 

 but all the drainage of the Ozarks goes from this divide either 

 north to the Missouri and Meramec Rivers or south to the 

 White and Arkansas Rivers, a very small area only being drained 

 eastwardly direct into the Mississippi River. 



In the region immediately adjoining the plateau the streams 

 have cut deep valleys and narrow gorges with innumerable ra- 

 vines. This is the most rugged part of the whole region, the 

 valleys reaching their maximum depth about midway between 

 the plateau and the border subregion with bluffs and cliffs 300 

 feet high in places. 



The Ozark border subregion is the hilly belt inclosing the 

 Ozarks, being less rugged, less stony, but broken up more or less, 

 and sloping gradually down to the prairie region or terminating 

 on the east and north in the bluffs of the Mississippi and 

 Missouri Rivers. The prairie region has never been a true, 

 treeless prairie; its name is applied simply because its topog- 

 raphy is of the same type as that of all the prairie regions 

 of the Mississippi Valley ; it is in fact the eastern border of the 



