PERSPECTIVE ON NINETEEN CENTURY CONTINENTAL MOLLUSCAN STUDIES THROUGH A TIMELINE OF CORRELATED EVENTS AND PUBLICATIONS – WHAT COULD WESTERN NORTH AMERICAN PALEONTOLOGISTS/GEOLOGISTS POTENTIALLY CONCEPTUALIZE BASED ON THE SCIENCE OF THE DAY?

A comprehensive integration of Hayden, Meek, and White's paleontological and geological research, incorporating others with less molluscan oriented careers and including prior related studies resulted in a late 1700s to early 1900s timeline of their administrative, public, and scientific writings in the context of other political, mapping, geological, and biological developments. Whenever possible, the timeline incorporated dates closer to the conception of ideas and field activities (e.g., reading before a society, letters to editors and administrators), providing dates earlier than the published volume and closer to the actual communication of ideas to learned colleagues.

Important European biostratigraphic concepts were available to antebellum geologists attached to western expeditions (e.g., Frémont, Warren, Raynolds) and were refined as territorial surveys (e.g., Hayden, Powell, Wheeler, King) made geologic sections and maps of the West. North American paleontologists and geologists were familiar with Lyell’s Principles of Geology; d’Orbigny’s proposed stages (effectively chronostratigraphic units), his use of type localities, and his recognition of species extinction and that of higher taxonomic categories; and William Smith’s mapping of large areas by correlating strata on the basis of fossils. Darwin gave rationale to Smith’s methods, while Huxley cautioned correlating similarly arranged strata and fossils from one location to another, as evolution could be applied to the fossil record. Gressly's facies had little application. Thus by the time Hayden and Meek finished their antebellum apprenticeship, they both might have been ready to discuss their observations in more conceptual terms (but generally did not). They were familiar with foreign authors with regard to taxonomy and certain aspects of stratigraphy. Hayden was convinced of a unique North American geologic period not represented in Europe. By the mid-1880s, White had discussed changing environments, geologic time, extinction, uniformitarianism (not using the word), and the relationships among species. Fossil continental molluscan taxonomy had not changed much if at all. Not until the end of the 1890s did paleontologists have an inkling from malacologists of how to proceed on parsing diversity either in space or time.