Bivalve shell

Horses’ heads

This is an internal cast of a fossil shell from the Portland Limestone. The shell itself has been dissolved away, leaving the impression of the inside of the shell complete with the hinge and muscle scar. The folklore name for these is ‘’osses ‘eads’, because they do resemble a horse’s head. The ‘teeth’ are the hinge between the shells, and the ‘eye’ is the muscle scar.

Find out more about bivalves on the molluscs pages.

Common name

Bivalve shell

Scientific name

Myophorella incurve


Molluscs > Bivalves


Portland Limestone

Time period

Upper Jurassic


145 million years

Where found

Probably Worth Matravers

Found by

Mrs Calkin


Swanage Museum

Accession number