PREFACE 



During the prosecution of the study herewith given of a fauna 



essentially new to the New York series of geologic formations, I have 



been under special obligation to Professor Albert L. Arey, of Brooklyn, 



the first to discover and record the presence of a Guelph fauna at 



Rochester, for the use of his collections, of which many specimens are 



here figured. In this place, also, I desire to make acknowledgment for 



courtesies received from Colonel C. C. Grant of Hamilton Ont. This 



work has, further, been essentially aided by the fine collections from the 



tough dolomites at Shelby, made by D. D. Luther, who has also contributed 



important stratigraphic details. 



John M. Clarke 



State Paleontologist 



