echinoderm ossicles indeed, but not Pentacrinus ... your Campanian fossils looks like the basal plates of the roveacrinid Applinocrinus ... you may check for this:
Jagt, J.W.M. (1999): Late Cretaceous-Early Palaeogene echinoderms and the K/T boundary in the southeast Netherlands and northeast Belgium - Part 2: Crinoids. — Scripta Geologica 116: 59-255. (cf. Plate 39, figs. 7-8)
these findings, as rightly written by Mike, probably are ossicles of Applinocrinus, a microcrinoid of Upper Cretaceous. To ensure that this is Applinocrinus, you should find or the radial plates or cups, which have a distinctive morphology .
These are apical plates of Applinocrinus (Saccocomidae, Roveacrinida). For specific assignment, you should compare to A. ramaraoi (described in India), but most likely to Applinocrinus cretaceus (Bather).
Could you tell us the site of sampling and the associated micro/macrofauna?