F. Carney — Wave-cut Terraces in KeuTca Valley. 329 



child,* who shows how the banks of glacial drainage streams 

 differ from the wave-cut cliff, f The latter is not so localized 

 as the former, nor, in general, so marked in development. 



Considerable effort was devoted to explaining the terraces in 

 question as the result of differential weathering. The other 

 explanation, ice-stream work, was easily eliminated. The 

 third interpretation discussed in this paper suggested itself 

 after it became apparent that neither of the other two was 

 pertinent. 



Stratigraphy of Bluff Point. \ 



The succession of formations as given in Bulletin 101 of the 

 1ST. Y . State Museum (which appeared after the close of the 



Fig. 2. View of west shore of Perm Yan branch about two miles north of 

 Cunning's landing. Shows terrace No. 2, and what is apparently the lowest 

 terrace altered probably by ice-erosion. 



field season during which this study of wave-cut terraces was 

 prosecuted), a report prepared by Luther, has been used by the 

 writer in checking up his field notes on the stratigraphy of 

 the area involved ; these notes concern only the lithological 

 aspect of the formations exposed, and since the slopes of Bluff 

 Point are rather sharp, the rock section is almost complete. 



The compact sandstone layer, referred to by Clarke and 

 Luther, about 125 feet above the base of the Cashaqua as 

 revealed in the Naples region, § appears near Tveuka Park and 



*N. Y. State Mas., 22d Rep. of State Geologist, pp. r23-r80, 1902. 

 ■j-Ibid., 21st Rep. of State Geologist, pp. r33-r35, 1901. 

 \ The Penn Yan Quadrangle will serve as an index map for this region. 

 §N. Y. State Mns., Bulletin 63, p. 31, 1904. 



