DAVID DALE OWEN (1807–1860) AND THE NAMING OF ARCHIMEDES, THE FIRST DESCRIBED FENESTRATE BRYOZOAN, A COMPLEX FOSSIL WITH IMPORTANT STRATIGRAPHIC AND ECONOMIC IMPLICATIONS

David Dale Owen carried out several and extensive geological surveys across Indiana, Iowa, Wisconsin, Illinois, and the Northwest Territory during a full but relatively short career that was only terminated with his death in 1860. Son of Richard Owen, the Scottish philanthropist, David lived and worked in New Harmony, Indiana, where he carried out research and taught others. In 1838 he published the important memoir A Geological Reconnoisance and Survey of the State of Indiana in 1837 and 1838 in which on page 13 he noted a unusual spiral-shaped fossil which he called ‘Archimedes'. Owen realized the stratigraphic and economic value of the fossil to coal-prospectors who would have had little difficulty in recognizing its distinctive shape. He made it known through his publications that the fossil-bearing limestone lay beneath the coal deposits and so once reached it was pointless sinking shafts and trial pits any deeper. Archimedes is now known to be a bryozoan, a colonial marine organism that was common in Mississippian Seas, and occurs extensively in a limestone that was locally termed the ‘Archimedes Limestone'. This horizon is now known as the Warsaw Limestone which is Mississippian in age and extends across several states in the Midwest. The genus Archimedes is also significant in that it was the first bryozoan described that is now placed in the Order Fenestrata. For the name, Owen adopted Charles Alexandre Lesueur's manuscript name, and this, combined with changes in spelling in subsequent editions of his work caused serious nomenclatural and taxonomic problems for later taxonomists and paleontologists, problems that were only cleared up in the 1950s. Recent advances in bryozoan taxonomy and morphometrics have yielded further information about Owen's complex and fascinating fossil.