766 A. C. VEATCH 



beds, they have not as yet been definitely recognized, but cer- 

 tain thick beds of stratified gravels, whose position could not be 

 satisfactorily determined in the short time that was spent on 

 this island, may prove to be its equivalent. The fact that beds 

 of Manhasset age have been recognized by Mr. M'. L. Fuller on 

 Montauk Point and Shelter Island greatly strengthens this sup- 

 position. On Shelter Island the beds are, moreover, known to 

 be underlain by fossiliferous clay. 



4. Wisco?isin deposits. — The whole surface of the island is 

 covered with recent morainal deposits. These have so masked 

 the older topography that it is quite morainic in character, 

 though the major topographic features are doubtless due to the 

 distorted older deposits. Where seen in clean sections they are 

 sharply nonconformable to the older deposits. They differ very 

 little from the normal deposits of the same period on Long 

 Island, and have a maximum thickness of about 50 feet. 



LONG ISLAND. 



For the purpose of this discussion the geologic succession on 

 Long Island may be stated as follows : 



Pre-Pleistocene. 

 Pleistocene. 



Pensauken (glacial). 

 Jameco (glacial). 

 Sankaty (interglacial). 

 Manhasset (glacial). 

 Wisconsin. 



Ronkonkona moraine.' 

 Harborhill moraine. 



Pre-Pleistocene.-— Th.& pre-Pleistocene formations concern us 

 mainly in that they form the surface on which the Pleistocene 

 beds were deposited. On the western part of the island, about 

 Astoria and Long Island City, on the East River, the crystalline 

 rocks out-crop. Eastward and southward they occur at increas- 

 ing depths beneath the unconsolidated beds. Such boring rec- 

 ords as have been collected in this part of the island indicate a 

 very irregular rock surface sloping southeastward at an average 



' Name proposed by Mr. M. L. Fuller in manuscript discussion. 



