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Specimens of Jurassic and Cretaceous Belemnoidea were analyzed and their paleotemperature record compiled from mass-spectrometric measurements. The data are compared with information assembled from other fields of investigation. It is demonstrated that from a subtropical climate in the later Jurassic, a more diversified one developed in the Cretaceous. From the rather cool conditions of the Neocomian, a temperature climax was reached in Albian times-to be followed by a decline attaining its minimum in Cenomanian waters. Later, another temperature climax occurred-in the Coniacian-Santonian. Subsequently, a gradual lowering of temperature took place during the Campanian and was succeeded by cool, stable conditions in the Maestrichtian. This picture of Cretaceous climatic change was derived from the analyses of Mesozoic material from Germany and Poland described in detail in the present paper and supplemented by examination of additional specimens from western Europe. It is possible that the late Cretaceous ...

The Wisconsin glacial stage is classified on the basis of stratigraphy into six glacial substages, named, from older to younger, Farmdale, Iowan, Tazewell, Cary, Mankato, and Valders. In this paper names are proposed for the intraglacial substages not previously designated, completing the sequence as follows: These divisions fit the natural succession and provide the basis for historical and climatic interpretations of a broad scope, be they glacial advances, pauses, retreats, stagnation, eustatic changes of sea level, events beyond the ice sheet, changes of biotas, climatic changes and climatic controls, and analysis of radiocarbon dating. Valley trains were deposited during active maximum and submaximum stands of the glaciers and were in part followed by glacial torrents. The latter occurred when the icecap was being reduced and sea level was being raised. Except in the case of the Valders, another refrigeration followed, but the climatic change that halted the advance of the Valders was revolutionary. ...