Today I have the calyx of a crinoid called Eucalyptocrinites rosaceus to show you. It comes from the Loogh Formation (Devonian, Givetian stage) near Berndorf, Germany. The calyx is round and squat with a bit or ornamentation. The arms are missing but you can see their attachment points.
These next few photos are the profile view of the calyx rotated about 30 degrees between images.
Thanks to Nils for the specimen