The shell of Sinoceras is like Michelinoceras in that it has a slender orthoconic shell .
The camerae are shorter and septal necks proportionally longer , reaching nearly a third the camera length .
The shell of Sinoceras is like Michelinoceras in that it has a slender orthoconic shell but the camerae are shorter and septal necks proportionally longer , reaching nearly a third the camera length .