Promicroceras planicosta (Sowerby)
Hand sized slab of grey limestone. On the upper surface are four Ammonites all of different sizes and all on slightly different levels. Unusual.
Jurassic, upper Sinemurian, Obtusum Zone.
Black Ven, Charmouth /Lyme Regis, Dorset.
Specimen : 16.5 x 12 cm.