A LIST OF DEVONIAN FOSSILS COLLECTED IN WESTERN 

 NEW YORK, WITH NOTES ON THEIR STRATI- 

 GRAPHIC DISTRIBUTION. 



BY ARTHUR W. SLOCOM. 



The material upon which this paper is based, was collected during 

 the month of September, 1904, and is now a part of the Paleonto- 

 logical collections of this Museum. Especial effort was made while 

 collecting, not only to obtain as complete a fauna as possible at each 

 locality visited, but to have the number of specimens collected of 

 the various species represent, as nearly as might be, their relative 

 abundance at the different localities. 



In the Hamilton or Middle Devonian rocks of Western New York 

 and Canada there are three well-defined beds of varying thickness 

 but of constant lithological characters. The upper of these beds is 

 a shale called the Moscow shale; the middle bed is a crystalline lime- 

 stone varying in thickness from i l /i to 3 feet, called the Encrinal 

 limestone; and the lowest bed is the Hamilton shale. The Encrinal 

 limestone is present at so many of the outcrops, and is so easily rec- 

 ognized that it serves as a datum line for correlating the shales either 

 above or below it. At none of the localities visited by the writer was 

 there enough of the beds exposed to give any idea of the thickness of 

 the series, but measurements made at other places by other authors 

 show that in a general way the beds may be said to gradually thin 

 out towards the West. Thus at *Utica, New York, where the meas- 

 ure was obtained from a well, Prosser found a thickness of 1,142 feet. 



At the fLivonia salt shaft in Livingston county, about 124 miles 

 west of Utica, Luther reports the thickness of the beds as 517 feet, 

 and at the f Crystal salt well near Wyoming, about 23 miles farther 

 west, a thickness of 407 feet. At % Eighteen Mile Creek near Buffalo, 

 about 45 miles west of Wyoming, Shimer and Grabau report that 

 the beds measure only 76 feet. At JThedford, Ontario, about 130 

 miles still farther west, a thickness of 81 feet is reported by the same 



•Am. Geologist, Vol. VI, p 202. 



t 47th N. Y. State Museum Report, p. 258. 



% Bull. Geol Soc. of Am., Vol. 13, p. 162. 



257 



