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 New York State Education Department

, Director

Memoir 14

THE EURYPTERIDA OF NEW YORK

JOHN M. CLARKE

RUDOLF RUEDEMANN

PREFACE

While the senior author of this work was engaged in the preparation of the monograph of the American Devonic Crustacea which constituted volume 7 of the Palaeontology of New York [1888], the forms of the Eurypterida there presented for consideration, led to the impression that it would be a service to paleontology to restate in detail the structure of this unique group of extinct creatures. The Siluric rocks of New York had proven so profuse in these remains that the material was not wanting for such analysis; the late Professor James Hall, who in 1859 had given the most intimate account of the eurypterids developed up to that time, concurred in the belief that the 30 years which had then passed would, with the aid of accumulated data and in the light of the contributions made by other writers, afford new facts worth recording. Not long after this Gerhard Holm published his very remarkable analysis of the structure of Eurypterus based on specimens from the Baltic Siluric and on the appearance of this exhaustive memoir it seemed that the anatomy of the group could hardly be supplemented except by the estimation 5