Rodzaj Bollandites Gordon, 1957
Gatunek typowy Opis Closely related to Bollandoceras. Conch discoidal to thick-discoidal with umbilicus moderately wide to narrow; concavo-convex growth lines consisting of non-crenulate biconvex transverse striae, which are in some species relatively strong; constrictions present and no spiral ornamentation; ventral lobe with V-shaped, very low median saddle and rather narrow, at its base as in Muensteroceras; its sides are subparallel in the apicad half, diverging orad; tips of branches of ventral lobe not diverging; first lateral saddle broadly rounded; adventitious lobe symmetrical and wide, with more or less sinuous sides including a broad angle, lying about in line with basis of ventral lobe. Synonimy Zasięg czasowy Carboniferous, Visean. Literatura Gordon. M. Jr. 1957. Mississippian Cephalopods of Northern and Eastern Alaska. Professional Papers, U.S. Geological Survey 283: 1-61, Washington. |
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