APTYCHUS
Source: 567
‖Ap″ty‐chus (�), n. [[NL., fr. Gr. ἀ priv. + �, �, fold.]] (Zoöl.) A shelly plate found in the terminal chambers of ammonite shells. Some authors consider them to be jaws; others, opercula.
Source: 567
‖Ap″ty‐chus (�), n. [[NL., fr. Gr. ἀ priv. + �, �, fold.]] (Zoöl.) A shelly plate found in the terminal chambers of ammonite shells. Some authors consider them to be jaws; others, opercula.