Promicroceras planicosta (Sowerby)
Hand sized slab of grey limestone. On one surface there are 4 beautifully preserved calcitic Ammonites all on different levels.
Jurassic, Upper Sinemurian, Obtusum Zone.
Black ven, Charmouth / Lyme Regis, Dorset.
Specimen : 16.5 x 12 cm.
