FLOWEKING PLANTS AND FEENS OF INDIANA. 557 



Crawford, Orange, Washington and Jackson, but attain their greatest 

 development in Floyd, Clark and Scott, where the Silver Hills and 

 Guinea Hills rise to 400 and 500 feet above the valley bottoms. In 

 Brown County the knob topography attains the highest absolute eleva- 

 tion in Weed Patch Hill, and the surrounding region is so rugged as 

 to have gained the title of the "Switzerland of Indiana." 



In addition to the massive and rugged moraine belts already de- 

 scribed, there are many morainic ridges of gentle slope and smooth 

 profile, conspicuous only upon the map by their influence upon 

 streams. Those which extend along the right bank of the St. Mary's, 

 upper Wabash, Salamonie, Mississenewa and upper White rivers are 

 typical examples. ' In this connection should be mentioned the form of 

 moraine known as boulder oelts — long, narrow, curving strips of coun- 

 try, thickly covered with large boulders. These occur in many coun- 

 ties in the northern half of the State. 



Dunes and Beach ridges are hills and ridges of sand or gravel, 

 either blown up by the wind or built up by the waves of lakes now 

 withdrawn. Such features are found in the region around the head of 

 Lake Michigan, the Kankakee basin, and the Maumee Lake basin, east 

 of Fort Wayne. 



All the valleys of Indiana are the result of stream erosion; most of 

 them by the streams which now occupy them. During the glacial per- 

 iod, however, the streams generally carried much more water than at 

 present. 



Gorges and ravines exist in great number and variety throughout 

 the Ohio slope, occurring along the White Water, White and Ohio 

 rivers, and all their tributaries. The eastern tributaries of the Wa- 

 bash in Fountain and Parke counties flow through very beautiful can- 

 yons, cut in massive sandstone. In valleys of this character rapids and 

 falls are very numerous. They occur upon nearly every stream empty- 

 ing into the Ohio, and vary in height from a few feet to sixty or eighty. 



Between the terraces of sand and gravel, which border the present 

 channels of our streams, and mark the heights at which they were once 

 able to deposit sediment, there are often broad "bottoms" or flood 

 plains, which furnish the best corn lands in the world. 



The surface of the northern plain is thickly sprinkled with small 

 lakes, which occupy irregular depressions in the surface of the drift 

 and are especially characteristic of the massive moraines. The whole 

 number can not be less than 1,000. The largest, Turkey Lake, in 

 Kosciusko County, has an area of five and a half square miles. 



The marshes and swamps exceed the lakes in number and extent. 



