344 



Not much need be said about the tributaries of the Wabash, for Lev- 

 erett has very fully discussed them. The details have uot been worked out, 

 and what is known was that most easily determined. Usually it is the 

 lower portions of these streams and the lower portions of their tributaries 

 that are well known, the headwaters being usually post-glacial and the pre- 

 glncial valleys covered with drift. 



The coarse of White river below the north line of Greene county, with 

 slight exc-eption, is so completely covered with drift that the course of the 

 preglacial stream can not be ascertained. For a few miles below Martins- 

 ville the present stream follows a preglacial valley. The river below Spen- 

 cer flows for a few miles in a narrow, shallow channel among the hills and 

 ridges, there being no definite preglacial drainage lines to control its course. 

 It occupies a preglacial valley from the mouth of Raccoon creek down to 

 Worthington, where it joins a wider valley two to two and one-half miles 

 wide, which trends south. From this point to its mouth, the course of the 

 stream is nearly coincident with a broad preglacial line. 



Bean Blossom creek, which Leverett has not included in his map of the 

 preglacial drainage of Indiana, is undoubtedly preglacial. This is the con- 

 clusion of Dr. E. E. Cummings and V. F. Marsters, both of Indiana Uni- 

 versity, who have worked in this region (69). 



The Patoka is very interesting on account of the fact that it is a 

 composite of the headwaters of four different stream systems. For shore 

 distances it follows a preglacial channel and then it suddenly crosses rock 

 surfaces which were formerly cols between the pi-eglacial streams. The 

 three upper stream systems emptied northward in preglacial time into the 

 White river. During the advance of the Illinois ice-sheet the mouths of the 

 stream were dammed, and lakes were formed. The water in the upper or 

 eastern lake flowed into the next west over some low sag in the divide and 

 this into the third. Whether the lake drained south over a sag into the 

 Ohio or dx'ained westward to the Wabash through some sub-glacial channel 

 is not settled, but Leverett inclines to the latter (64: 101-2). 



The Ohio river (65; 183) below Madison is thought to be preglacial 

 through its entire course along southern Indiana, except probably for a 

 short distance at Louisville, as J. Bryson (12) and C. E. Siebenthal (91) 

 have discovered. This is Leverett's conclusion also, but he says further, 

 "A coiu'se about as direct is found in a line leading west from Madison, 

 Indiana, alons: the IMiiscatatuck. to the East White and White rivers and 



