484 GEORGE W. STOSE 



680-foot terrace probably represents an earlier halt of short duration 

 and the 560-foot lowland a very recent broadening of the limestone 

 valleys. 



There are recognized in this area, therefore, the Schooley pene- 

 plain at 2,000 to 2,100 feet elevation forming the mountain summits, 

 the Harrisburg peneplain at 750 feet on the higher shale hills, a pene- 

 plain at 620 feet on the lower shale hills possibly equivalent to the 

 Somerville plain of New Jersey, and intermediate uncorrelated ter- 

 races at various levels. 



George W. Stose. 



Washington, D. C. 



