1. It bears pronounced concentric ribbing around its strongly coiled exogastric shell. 2. The shell is a compressed, exogastric cyrtocone, section sub ovoid. 3. The Cyrtogomphoceratidae are endogastric, the Westonoceratidae, exogastric . 4. "Ulrichoceras " is also considered the source for the exogastric Westonoceratidae. 5. The phragmocone is rapidly expanding and strongly exogastric . 6. The shell of " Gaspocyrtoceras " is a coarsely annularted exogastric cyrtocone. 7. Both are straight shelled or slightly exogastric . 8. Other Ordovician families are the broad and beviconic Cyclostomiceratidae and exogastric Bassleroceratidae, rounding out the Ellesmeroceratina. 9. Both are strongly compressed, exogastric brevicones with the ventral side more narrowly rounded than the dorsal. 10. The shell is cyrtoconic, exogastric , more strongly curved than in " Kindleoceras ".
