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the complete oxidation of the glauconite was accomplished. Toward the close of the Redbank epoch finer sediments prevailed, and there is every evidence that land-derived materials found ingress to the area of deposition in gradually lessening amounts.

The succeeding Rancocas epoch was a time of slow accumulation of continental materials so that the production of glauconite went on unhindered. During the latter portion of the epoch, however, there must have been a great profusion of animal life, for the deposits show a marked admixture of carbonate of lime, while in many instances the shells are still in an excellent state of preservation. The formation of glauconite was not interrupted, although its relative proportion is at times much diminished by the great amount of carbonate of lime which may in some instances reach eighty per cent. of the whole.

The Manasquan epoch was characterized throughout by the constant formation of greensand beds, although land-derived materials in considerable amounts reached the area of deposition during the early portion of the period.

No very marked changes apparently affected the region toward or at the close of the Cretaceous, but the same conditions persisted on into the Eocene, as shown in the Shark River formation, during which period similar deposits with very different types of animal remains were accumulated. At the close of the Shark River epoch the conditions favorable for the formation of greensand ceased, not to be again revived during the period of formation of the coastal deposits in New Jersey.

The succeeding epochs gave proof of much shallower waters, while the ancient Cretaceous-Eocene sea floor frequently stood above sea level and along its landward portions constantly lost as the result of erosion. As the land rose higher and higher in late geological history further inroads were made until the deeper portions of the ancient sea bottom were exposed by the forces of denudation.

The source of the materials which constitute the several formations of the coastal region of New Jersey has not been