thiolliericrinid crinoids from the lower cretaceous of crimea

— 637 —surface. The height of the centrodorsal is about equalto the height of the radial ring. 2 to 3 cirrus socketsare under each the radiais. 11 to 12 sockets in all.Some of the sockets are replaced by structureless fossae.The free surface of the centrodorsal between thecirrus sockets is granulated like that of the externalradial surface. The lower centrodorsal face, in all examinedspecimens, is poorly preserved. It is convex,ovate-oblong and has a fulcral ridge on whose bothsides two slit-like furrows are marked, surrounding intheir turn by two marginal ridges.D i m e n s i o n s :Ht = 5.5 - 8.4 mm ; Dt = 7.8-11.8 mm ; Dc = 5.3- 9.5 mm ; A f = 50° ; H r : H t = 0.10 - 0.18 ; Bf : Lf= 0.41 - 0.45.C o m p a r i s o n :T. belbekensis resembles T. favieri after its centrodorsalconstruction (one row of sockets, roughly twounder each of the radiais). The species under discussiondiffers from T. favieri having relatively lowradiais, a granulated external surface and fossae on itscentrodorsal.M a t e r i a l s :8 calyxes, 2 radiais, 1 centrodorsal and 11 brachials(see table 1).D i s t r i b u t i o n :Berriasian ; Crimea.Fig. 5 — Calyxes and brachials of Thiolliericrinus belbekensis (x 3).A - holotype CK-85-1 (calyx from side and below).В - CK-85-9 (centrodorsal with two basais from above).С - CK-85-10 (primaxillary from above and below).D - CK-85-13 (secondaxillary from above).E - CK-85-14 (secondaxillary from below).F - CK-85-17 (tertibrachial from below).Coupes dorsales et brachiales de Thiolliericrinus belbekensis.A - holotype CK-85-1 (coupe dorsale vue de côté et en dessous).В - CK-85-9 (centrodorsale avec deux basales, vue en dessus).С - CK-85-10 (primaxillaire, vue en dessus et en dessous).D - CK-85-13 (secundaxillaire, vue en dessus).E - CK-85-14 (secundaxillaire, vue en dessous).F - CK-85-17 (tertibrachiale, vue en dessous).