Summary.  Anthracoceras  is restricted to forms with entire, undenticulated sutural lobes and a
marked forward swing of the transverse striae over the lingua.  Anthracoceratites gen. nov. is
proposed tot forms with strongly bilobate transverse striae and a tendency for the lobes to be
denticulate.  Anthracceratoides gen. nov. is proposed for forms with more or less straight
transverse striae on the flanks, and non-denticulate sutures.