Florida Bay
The part of the Miami Limestone forming the Atlantic Coastal Ridge and the lower Florida Keys is an oolitic grainstone which includes fossils of corals, echinoids, mollusks, and algae. The oolitic formation in the lower Florida Keys has less quartz sand and fewer fossils than does the oolitic formation on the mainland. Based on those differences, Mitchel-Tapping divided the Miami Limestone into the Fort Dallas oolite on the mainland and under northern Florida Bay, and the Key West oolite, under southern Florida Bay and the lower Florida Keys. The fossils in the formation underlying the Everglades, which does not include any ooids, consists primarily of a single bryozoan species, "Schizoporella floridana".