This little cluster of coprolites was found on a beach near the mouth of Middlesex County beach on the Rappahannock River. Crustaceans such as ghost shrimp and crayfish produce fascinating rod-shaped fecal pellets containing little canals. The canals can have all different shapes. These have crescent-shaped canals.
The pellets likely accumulated in an empty burrow, shell or other crevice near the home of crustacean that created them.