Promicroceras planicosta (Sowerby)
Base cut freestanding piece of the famous Ammonite Marble from Marston Magna. There are 6 complete specimens with white shell preserved and other remains.
Jurassic, Upper Sinemurian, Obtusum Zone., 'Ammonite Marble'.
Marston Magna, Somerset.
Specimen : 8 x 4.3 x 3 cm.
