1884. Proc. Zool. Soc., p. 365.
Genotype: Gegania pinguis Jeff. op. cit. pl. 27, figs. 10, 10a. Recent, off Portugal.

Gegania has been generally submerged in Tuba Lea, 1933. Both Sherborn and Neave give this name as preoccupied in Vermes by Renier, 1804, and by Fabricius, 1823, in Mollusca. Sherborn stated, however, that Fabricius did not define his genus and that it was accompanied only by 5 specific names, all nomina nuda. Consequently Tuba Fabricius is invalid as itself a nomen nudum, Tuba Renier still remains, and Lea's generic name cannot be used unless Renier can be disposed of. There is an available name for the group in Gegania Jeffreys. Concerning this, Dall (1892, p. 319) wrote “Gegania is an absolute synonym of Tuba; both have a sinistral nucleus, which is, however, so far immersed, or of such small coil, as to appear to a casual examination merely gibbous and dextral. I have verified this fact by most careful study of the typical specimens of Lea and Jeffreys.”

Mathilda prima Laws, 1935, from the Hampden Bortonian, can be classed under Gegania. It has not the high spire of Mathilda and its protoconch is not known. Mathilda kaiparaensis Laws., 1941, appears to belong to Opimilda Iredale, 1929, type M. decorata Hedley.