THE GLACIAL LAKE CHICAGO. 439 



At Dyer, Indiana, the beach is crossed by a small stream, which 

 exposes the following section: 



Section of beach in bank of stream at Dyer, Indiana. 



Feet. 



Sand G 



Sandy gravel 6 



Bluish sandy gravel, with water 3-4 



Yellowish-gray clay 6 



Total 22 



At Schererville the sand has a depth of about 25 feet on the crest of 

 the ridge, but only 12 to 15 feet at the inner border, and thins out to about 

 8 feet a half mile north of the crest. 



South of Michigan City the gravel in the beach is shown by wells to 

 have a depth of about 12 feet and rises 6 or 8 feet above the bordering 

 marsh on the south. This appears to be somewhat more than the usual 

 depth of gravel along this portion of the lake border. 



At the point where the gravel ridge comes to the lake shore north of 

 New Buffalo, Michigan, the gravel is 10 or 12 feet in depth. Sections of 

 two wells in sec. 36, located on this ridge, also show about 12 feet of gravel 

 and sand. In one well a bluish clay is interbedded with the lower portion 

 of the gravel. In another the gravel is underlaid by 2 or 3 feet of sand, 

 and this deposit rests on the till. 



A well on the beach west of Sawyer penetrated 6 feet of sand, beneath 

 which was a water-bearing gravel, which, at a depth of 6 feet, furnishes 

 sufficient water to supply several families. 



In the sand ridge at Overisel, in northern Allegan County, wells often 

 pass through a bed of brush and herbaceous vegetation at the bottom of 

 the sand, a feature which indicates that the sand has encroached upon a 

 land surface at that point, and supports the view, above suggested, that it 

 has been drifted by wind slightly above the general level of the old water 

 surface. 



Remains of animal life have been reported only at a few points along 

 the entire length of the portion of the beach examined, and none have been 

 observed by the writer. Mr. Haas reports that shells of the size of Unios, 

 and also smaller molluscan shells, have been found in a bed of sand at the 

 bottom of the gravel pit which he has opened near Oak Park. Upon the 

 request that he preserve any shells which might subsequently be found, he 



