[238]

Amphicyclia = Circular shell with spines on both sides; ἀμφί, κύκλιον.

[239]

Trigonocyclia = Triangular shell with circular rings; τρίγονον, κύκλιον.

[240]

Staurocyclia = Circular shell with four crossed spines; σταυρός, κύκλια.

[241]

Astrocyclia = Stellated circular shell; ἄστρον, κύκλιον.

[242]

Coccocyclia = Circular shell with nucleus; κόκκος, κύκλιος.