54 CHICAGO ACADEMY OF SCIENCES. 



13. On Eighteenth and Robey streets, Chicago. The surface 

 of arching layers is roche moutonneed. The prominent portions 

 of the surface are striated, the bearing of the striae ranging from S. 

 52 degrees to S. 57 degrees W. 



14. Covel's quarry near Elmhurst, Sec. 17, Tp. 39, R. 12 E. 

 The surface is planed quite extensively and covered with a multi- 

 tude of striae, bearing S. 63 degrees W. 



15. Joliet, bearing 20 degrees north of west. An exposure of 

 striae with this remarkabje bearing was found on ledges in the 

 Des Plaines valley, a short distance southeast of the State Peni- 

 tentiary. The ledges stand 10 to 20 feet above the valley bottom 

 and several striated surfaces were found, with small grooves, as 

 well as fine striae. 



16. Du Page blufif, near C, R. I. & P. Railway bridge, east 

 of Minooka. Prof. J. A. Udden reports an observation of heavy 

 glaciation, with grooves bearing about southwest. 



17. Near Wilton, quarries are opened, which expose surfaces 

 heavily glaciated with grooves bearing about S. 40 degrees W. 



