GEOLOGY OF HAMILTON, WARREN AND WASHINGTON COUNTIES 151 



kept separate. They have been identified as follows by Mr Van 

 Ingen: 



No. 5 3 feet. Ostracoda, abundant 



Turrilepas canadensis Woodward 

 No. 4 2 feet. Lamellibranch 

 No. 3 2 feet. Small Ostracoda in abundance 

 No. 2 2 feet. Calymmene senaria Corvrad 

 No. 1. Indistinct Lamellibranch 

 Calymmene senaria Cowrad 



No graptolites were found by us, but Dr Ruedemann mentions 

 Diplograptus foliaceus Murch. (=p r i s t i s Hall) and 

 also fragments of Endoceras, and casts probably of 

 31 o d i o 1 o p s i s . He regards the rock as lower Utica. 



The dips of all the beds are so low as to be with difficulty de- 

 termined. A reading for the Potsdam was obtained of 3° to 4°n. 

 The Calciferous dips slightly to the west. The Trenton strikes 

 n 57 e and dips 7 n w when corrected for magnetic vari- 

 ation. In the Utica a supposed cleavage gave a reading n 

 52 e, 15 n w. It is evident from this that the dips are to the 

 northwest, and that with the faulting there has been a slight tilt- 

 ing in this direction. At the same time it is surprisingly small, 

 and the blocks must have dropped very easily. It is a specula- 

 tive question as to whether the several blocks of paleozoics are 

 themselves faulted with regard to each other. They either are, 

 which we doubt, or else the cross-section of each is very small, 

 and we must infer that the several formations have thinned 

 greatly in this area, from their normal magnitude. The uncer- 

 tainty of these relations is the reason for not drawing a cross- 

 section. 



In the interpretation of the deposits, the presence of the lime- 

 stones would indicate that the estuary if present, in accordance 

 with the views advanced for the Champlain side, must have been 

 a very broad one; and we are quite free to admit that the present 

 walls of the valley are fault-scarps. There is no question of this; 

 but that a land area existed to the north and at no great distance, 

 we think is equally assured. The Potsdam is a shore deposit, and 



