"Pygaster semisulcatus, Ph.; Inf. Oolite, Cheltenham." — Encyclopedia Britannica, 1893

Fossil Echinidea

"Pygaster semisulcatus, Ph.; Inf. Oolite, Cheltenham." — Encyclopedia Britannica, 1893

"1, Turret, St. Peter's Church, Oxford; 2, Turret, Rochester Cathedral; 3, St. Mary's Church, Cheltenham; 4, Bayeux Church, Normandy." — Chambers, 1881

Spire

"1, Turret, St. Peter's Church, Oxford; 2, Turret, Rochester Cathedral; 3, St. Mary's Church, Cheltenham;…