The Oolitic Polyzoa have been very little studied in this country. They are badly represented in our museums, and no systematic account of them has been given by any English writer. Their remains, however, are both abundant and often well-preserved in the Pea-grit beds of the Inferior Oolite near Cheltenham, and in the Forest-marble beds near Bath. Some Inferior Oolite beds near Metz, and the Forest-marble beds near Caen in Normandy, are still more prolific, and the produce of these several beds has furnished a very full illustration of the more prevalent forms of this class which lived in the Oolitic seas.