Procidaris lobatum Wright 1861 ( formerly Miocidaris )
rectangular piece of grey limestone. The upper surface shows about a dozen spines from a regular Echinoid as well as a few isolated plates from the test. Nice detail under magnification. Unusual.
Jurassic, lower Sinemurian, Bucklandi Zone.
Hock Cliff, River Severn, Fretherne, Gloucestershire.
Specimen : 9 x 5.5 cm.