THE ILLINOIAN ICE INVASION 305 



general surface of the country; bowlders, however, are much more numerous' 

 in the course of the obliterated stream than in any other part of the diluvium 

 exposed to view by the cut for the road. 



"In the silt, removed for the passage of the national road, sticks and other 

 vegetable matter were found; and in portions of this fluviatile deposit which 

 I have examined, I have detected at various times, small soggy pieces of wood, 

 such as we find at the bottom of existing waters; also fragments of the ribs of 

 leaves and their nervous ramifications, and a well characterized piece of pine. " 102 

 No shells were found. 



Wood has been found at Springboro, 44 miles west of Richmond, Wayne 

 County, at a depth of 14 feet. Wood with marks of the teeth of the giant 

 beaver (Castoraides) was also found near Richmond. Some of the wood was 

 thot to be pine; other fragments resembled Platanus occidentalis. Wood was 

 also found in Madison County, at a depth of 27 feet; it was thot to be elm. 



Leverett 102a records interglacial deposits in Putnam and Owen counties, but 

 remarks that he is hardly prepared to express an opinion as to the age of the 

 buried soils in southern Indiana. The Sangamon appears to be represented 

 in Putnam County, a ravine exhibiting the following section {op. cit., p. 63) : 



Surface silt or clay, white, pebbleless; apparently a correlation of the main loess de- 

 posit of the Mississippi basin 4-6 feet 



Soil, black, gummy, or gumbo, with quartz pebbles, representing apparently 



the Sangamon Interglacial soil 1-3 " 



Till, brown, generally with deeply weathered surface, apparently of Illinoian age.... 3-15 " 



Gumbo, black, changing to blue or gray below; generally containing a few pebbles.. 1-8 " 



Till, brown, extending to bottom of ravine, in places changing to blue; exposed 5-10 " 



"Twenty feet or more of the black mucky material is reported beneath the 

 upper sheet of till in certain wells in the region, but no exposure exceeding 8 

 feet was found in ravines. " 



"In La Grange County, a well about four miles south of La Grange, on the 

 farm of Dr. Drake, is reported to have penetrated a buried soil. The records 

 of the borings are as follows " {op. cit., p. 145) : 



Record of Prospect Boring at La Grange Jail 



Till, yellow 15 feet 



Till, blue, with thin beds of sand 50 " 



Mould or soil, brown (Sangamon?) 4 " 



Gravel, cemented 5 " 



Gravel, loose, with water 8 " 



Till, blue (Illinoian?) 45 " 



Gravel, cemented 8 " 



Sand and gravel, dry, or sandy till 70 " 



Total depth 205 feet 



102 Plummer, Amer. Journ. Sci., (i), XLIV, pp. 286-287. 

 io» Mon. LIII, U. S. Geol. Surv., pp. 64-71, and elsewhere. 



