ABSTRACT
Of the five Shattuck Zones found within the St. Mary’s Formation, four contain well-preserved molluscan fossils. These include Shattuck Zone 20 (the Conoy Member), Shattuck Zones 21 and 22 (the Little Cove Point Member), and Shattuck Zone 24 (the Windmill Point Member). The prominent sandstone ledge along the St. Mary’s River (the Chancellor Point Sandstone), separated from the underlying Shattuck Zone 24 by a major unconformity, also contains some well-preserved mollusks (see Chapter 2). Of all these units, the Windmill Point Member contains the richest and most diverse molluscan fauna, with the largest number of species found in the entire Chesapeake Miocene.
