Guelph fauna in the state of New York,

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