They had been found in Latchford's open iron ore pit in the Arundel Formation at Swampoodle near Muirkirk in Prince George's County, Maryland. Tyson let them be studied by the dentist Christopher Johnston, professor at the Baltimore Dental College, who cut one tooth in half and thereby discovered a characteristic star-formed cross-section.
Fossils of the teeth were found in Latchford's open iron ore pit in the Arundel Formation at Swampoodle near Muirkirk in Prince George's County, Maryland. Tyson permitted them to be analyzed by dentist Christopher Johnston, a professor at the Baltimore Dental College, who bisected one tooth and revealed a characteristic star-shaped cross-section.