The occurrence of perforations due to Lithophagous mollusca has been frequently observed in the Oolitic rocks, viz. in the Inferior and Great Oolite, Cornbrash, Coral-rag, and Portland beds. During a recent visit, with some of the students of the Agricultural College, Cirencester, to a quarry near there, further evidence of a similar fact was obtained. The quarry is situated near the canal on the farm land of Mr. Sargeant, and has been long worked for road stone and building stone, and, according to the Geological Survey, belongs to the Forest Marble division of the Great Oolite series, and exhibits the structure known as “false-bedding or oblique lamination,” and occasionally the flagstones in this and other neighbouring quarries show ripple-marks and tracks of marine animals.
IV.—On the Occurrence of Boring Mollusca in the Oolitic Rocks