Previous investigations of Mississippian St. Louis and Ste. Genevieve limestones in southwestern Kansas have suggested deposition in shallow marine environments exclusively. However, recent work has determined that these formations also contain a heretofore unrecognized eolian facies. Cross-bedded eolianites, made up of well-sorted ooid, skeletal, and peloid carbonate grains mixed with siliciclastic sands, reach 100 ft (30.5 m) thick in an area encompassed by seven southwestern Kansas counties. Cross-bed sets average about 1 to 3 ft (0.3 to 0.9 m) thick, but some reach 9 ft (2.7 m) thick. Foreset laminae, which are inclined approximately 16° to 20°, were formed by eolian grainfall processes. Thin, continuous laminae with inversely graded (texturally and compositionally) grains are abundant and interpreted as subcritically climbing translatent strata formed by migrating wind ripples. St. Louis subtidal grainstones commonly contain fragmented, large skeletal grains and are both cross-bedded to burrowed and moderately sorted. In contrast, the eolianites are well sorted and lack any coarse-grained bioclasts. All carbonate grains in the eolianite deposits are extremely abraded and well rounded. Indirect evidence suggesting an eolian origin includes features interpreted to represent rhizocretions, paleocaliche crusts, and a brecciated eolianite thought to have formed by surface weathering of a partially cemented dune ridge.