1892.] NEW YORK ACADEMY OF SCIENCES 43 



mergence which amounted to 100 feet at Croton and 340 feet at 

 Schenectady. Upon the re-elevation of the hxnd they were 

 much eroded by the Hudson River. 

 The section involved is 



Fine stratified yellow sand, 



Yellow clay, 



Blue clay. 

 They are underlain by modified drift, till or bed-rock. At the 

 mouths of the tributary streams deltas are found. The clays 

 are from 10 to 243 feet thick, and the blue is weathered to yellow 

 in the upper portion of the bank. (See H. Ries, Trans. N. Y. 

 Acad. Sci., Nov. 1891.) 



Glaijs of the Delaware and Susquehanna Watershed. 



At Breesport, near Elmira, is a bank of blue clay rising from 

 the valley to a height of 50 feet. It was formed when the 

 valley was dammed up. Subsequently the stream has eroded it 

 so that now all that remains is a narrow strip which forms a 

 sort of a terrace along the side of the valley. 



A similar deposit is found at Newfield, south of Ithaca. A 

 moraine crosses the valley a mile or two south of it. 



An interesting bed of clay occurs at Levant, Chautauqua 

 County. It occupies several acres and is probably of post-gla- 

 cial age. The section as determined by artesian well borings is: 

 Yellow sand 4 feet. 



Quicksand 

 Yellow clay 

 Blue clay 

 Hard pan . 



4 inches. 



5 feet. 

 70 feet. 

 — feet. 



Total thickness ... 83 feet. 



The owner of the clay bed informed me that leaves were (>ften 

 found between the layers of the clay at a depth of 15 or 20 feet. 



Staten Island Clays. 



The clays of Staten Island are chiefly Cretaceous, as proven 

 by the fossils found in them. (A. Hollick, Trans. N. Y. Acad. 

 Sci., Vol. xi.) The chief outcrojis are at Kreischerville, Green 

 Ridge and Arrochar. Besides the clay there are several kaolin 

 deposits. 



In many instances the clays have been much disturbed by the 

 passage of the ice over them, and in some cases the sections 

 show overthrown anticlines, as on the Fingerboard Road at 

 Clifton. 



Mr. "NV. Kreischer informed me that the clay at Kreischerville 



curs in isolated masses or pockets in the yellow gravel and 



