Both are strongly curved with a notable rate of expansion; ventral sides, as with the previous genera, are on the outside, convex curvature, making them, again, exogastric.
32.
The shell of " Simardoceras " is a moderately expanding exogastric cyrtocone, said to resemble a rather large " Oncoceras ", but with a siphuncle that is definitely discosorid.
33.
""'Conostichoceras " "'is an exogastric, breviconic oncocerid included in the family Nothoceratidae, known from the Middle Devonian of central Europe and Upper Devonian of Australia.
34.
""'Bassleroceras " "'is an elongate upwardly curved, exogastric, genus with the venter on the under side more sharply rounded than the dorsum on the upper.
35.
""'Cyrtonybyoceras " "'is a genus of slightly exogastric members of the Wutinoceratidae, a family of actinocerids and probably derived from an earlier " Wutinoceras ".
36.
Shells are rather small, reaching lengths of about 12-15 cm ( 5-6 in ); elongate with an upward, exogastric, curvature-like a rocker-and subcircular to laterally compressed cross section.
37.
"Blakeoceras " is an early nothoceratid possibly derived from " Perimecoceras " which has its origin in the Oncoceratidae, and is the likely source for the other exogastric nothoceratids with more greatly expanded shells.
38.
""'Tripteroceras " "', the type genus, named by Hyatt ( 1884 ) is characterized by a small, straight or slightly exogastric shell with a broad, depressed triangular cross section.
39.
The shell of " Blakeoceras " is moderately curved ( cyrtoconic ) with the ventral side on the outer curvature ( exogastric ) Chambers in the phragmocone are short and wide, separated by straight, close spaced septa.
40.
Oncoceratidae are characterized by generally compressed, cyrtoconic, and breviconic shells with an exogastric curvature such that the ventral profile is convex or more so than dorsal, and in which the siphuncle is generally empty and located ventral of the center.
