250 



ROLLIN T. CHAMBERLIN 



on the hillside ledges, though those in the ravine which were buried, 

 escaped. 



2. The second set of striae formed by the red ice trend about 

 S. 40 E., with some S. 45 E., and even S. 49° E. These stria? are 



Fig. 3. — Map showing the glacial striae of the St. Croix Dalles quadrangle 



interpreted as the work of the ice-sheet which had its front at the 

 Alden moraine. This set is the most persistent in the region, sug- 

 gesting vigorous ice-work at this time. 



3. The third, and most recent, group of striae vary from S. 63 E. 

 to S. 8o° E., and are thought to have been engraved while the St. 

 Croix moraine was being formed. A comparison of the three sets 

 shows that the first possessed most nearly the direction of main move- 



