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Three fundamental questions have confronted paleoceanographers from the beginning of their North American explorations. What was the size and timing of ancient epicontinental seas: large and long-lasting or small and brief? What characterized the distribution of biotas and sediments at any one point in time: a multitude of complex facies patterns or a more spacially homogeneous cover? What promoted continental foundering: eustatic changes in sea level or relative changes in sea level brought about by regional tectonics? These questions have been debated by North Americans since the middle 1800s in response to various new insights, usually coming from abroad but often elaborated into substantial contributions of equal standing. Contemporary facies zones in Mediterranean biota found by the Englishman E. Forbes attracted the notice of geologists as early as 1844. C. Whittlesey was among the first to apply the bathymetric scheme of Forbes to the interpretation of American Paleozoic strata in 1851. The outstanding “native” innovation of the period was J. Hall's geosyncline concept, which is reflected in the earliest map of Paleozoic North America made by T. C. Chamberlin in 1881. Another wave of influence spread from the late 19th century work on stratigraphic facies patterns by the German J. Walther. A. W. Grabau is best remembered as Walther's foremost American champion against the formidable layer-caker E. O. Ulrich in the first decades of the 20th century, but he also made pioneering contributions of his own on Paleozoic sea level studies and global paleogeographic reconstructions. Charles Schuchert was the consummate paleogeographer of this period. Meanwhile, the term “cyclothem” was coined by J. Marvin Weller in 1930 for recurrent Carboniferous strata in Illinois. Controversy fast erupted over a glacial as opposed to tectonic mode of origin for these cycles. In 1964, A. B. Shaw restimulated interest in Paleozoic oceanography through his reformulation of Walther's ideas. Novel additions included a model for epeiric sea carbonates and the methodology for graphic correlation. Invoking studies by C. G. J. Petersen on recent communities in Danish waters, A. M. Ziegler added new emphasis to paleobathymetry based on fossil communities. As was in Grabau's case, this interest eventually led to larger concerns with global paleogeography. Although the same questions are still debated today, the foregoing periods set the stage for a modern, more interdisciplinary approach to Paleozoic oceanography.