n.1.(Paleon.) A Silurian fossil, formerly supposed to consist of eggs.
Webster's Revised Unabridged Dictionary, published 1913 by G. & C. Merriam Co.
References in periodicals archive ?
Nitecki (1970) regarded Mastopora as a synonym of Cyclocrinites (as are Nidulites Salter, Pasceolus Billings, Cerionites Meek & Worthen and Lunulites Owen), but due to the absence of 'covering plates' or 'membrane' and branching of laterals in Mastopora (Eichwald 1840; Maslov 1956; Korde 1963), we consider here Mastopora and Cyclocrinites as separate genera.