Unless the carcasses were covered rapidly by sediment, they would have been eaten by predators, or the bones would have been scattered by surf or by tidal scour. The public beaches on the shore of Calvert County are a rewarding area for collectors of well-preserved fossil shells and sharks teeth. Sometimes small, very round holes will be noted in the shells. These were caused by borers that attacked the living Mollusca, and are not man-made. In general, the fossil shells may be distinguished from present day forms by the fact that their shells are usually thicker and are chalky white or gray.
Modern shells are more colorful and often are glossy.
The most comprehensive guide for the identification of specimens is the book Miocene Plates , the companion volume to the report Miocene Text . A smaller and simplified version of these two books, Miocene Fossils of Maryland , by Harold E. Vokes is useful. All of these are publications of the Maryland Geological Survey. Collecting at the base of the high cliffs is not recommended. Access to the area is difficult, and most of the land is privately owned.