Savageoceras
Encyclopedia
The genus Savageoceras is a barrandeoceratid first known from the Middle Silurian
of Illinois consisting of rapidly enlarging, depressed cyrtocones with a trapazoidal section; ventral side wider and flatter than dorsal; sides converging on dorsum. Sutures have slight lateral and ventral lobes and ventrolateral saddles. The surface is covered by transverse striae and has riblike annulae that are more prominent at the ventrolateral shoulders but otherwise vaguely defined. The siphuncle is central; interior unknown.
Silurian
The Silurian is a geologic period and system that extends from the end of the Ordovician Period, about 443.7 ± 1.5 Mya , to the beginning of the Devonian Period, about 416.0 ± 2.8 Mya . As with other geologic periods, the rock beds that define the period's start and end are well identified, but the...
of Illinois consisting of rapidly enlarging, depressed cyrtocones with a trapazoidal section; ventral side wider and flatter than dorsal; sides converging on dorsum. Sutures have slight lateral and ventral lobes and ventrolateral saddles. The surface is covered by transverse striae and has riblike annulae that are more prominent at the ventrolateral shoulders but otherwise vaguely defined. The siphuncle is central; interior unknown.