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Hook. The text contains an historical sketch in which the work of past investigators is briefly cited, and reference made to the various views upon the classification and correlation of the several formations. A second chapter is devoted to a consideration of the physical features of the coastal plain, following which is an extended statement in regard to the stratigraphical characteristics of the formations found there. Although an attempt is made to make the classification of the deposits coincide, so far as it is possible, with the investigations of the late Professor Cook, yet some changes of importance are considered to be necessary. The name Raritan formation is proposed in place of the wholly inadequate term Plastic Clay, and the Upper Marl bed, which is in part Cretaceous and in part Eocene, is divided into Manasquan Marl and Shark River Marl respectively. The division of Yellow Sand proposed by Professor Cook is not held to be an independent formation, but is included under the Manasquan Marl. The Miocene is considered to be extensively developed in New Jersey. Although fossils have been found at only a few points, they are thought to be sufficient in number to indicate a series of deposits several hundred feet in thickness and many square miles in surface exposure.

In summing up his statements in regard to the relation of the several formations, Professor Clark says, "the deposits of the coastal series of New Jersey show complete conformity from the bottom of the Raritan formation to the top of the Upper Marl bed, while no wide-reaching dislocations of the strata have been observed at any point. The strike follows a nearly continuous trend of N. 50 E., while the dip is twenty-five to thirty feet in the mile to the southeast. Overlying the Upper Marl bed unconformably is the Miocene, whih possesses the same general structural and stratigraphical features as the earlier members of the series."

The origin of greensand, which characterizes so many of the coastal plain formations of New Jersey, is fully considered, the results by Professors Murray and Renard, of the Challenger Expedition, being given with much fullness. The geological distribution of greensand is briefly reviewed, and the character of the New Jersey deposits more fully considered. Three colored plates are reproduced from the Challenger Expedition report on Deep-Sea Deposits, to illustrate the mode of formation of glauconite.

The object of this paper is to ascertain the length of the "deglaciation interval and perhaps interglacial epoch." The ice of the maximum period of glaciation affected this region but slightly. In some cases the glacial sand and gravels were deposited in ridges transverse to the streams' courses, thus damming the streams and producing small lakes. Sometimes the barriers were so