Fig. 12

Cups of Orthogonocrinus apertus Peck (a–g, i–l) and Roveacrinus peracutus Peck (h), upper Duck Creek Formation, Mortoniceras rostratum Zone (upper Albian); Saginaw Quarry, Fort Worth, Texas. a Lateral view of cup with unequal interfacet processes and partly broken aboral part, M11606. b Adoral view, M11599. c Oblique-adoral view of cup broken below facets, M11600. d Cup broken vertically and aborally, with partition separating small upper and large lower body chamber, M11597. e Aboral view of broken cup, partition with five peripheral radial openings and a central opening connecting the two chambers; M11607. f Small, nearly intact cup, interfacet processes low; M11639. g Smallest cup composed of bulging radials with intact base, suggesting presence of basals; M11691. h Broken cup of Roveacrinus peracutus, lateral view; M11605. i Lateral view of cup with equal interradial processes, M11601. j Lateral view of broken cup with unequal interfacet processes, M11603. k Lateral view of broken cup with additional vertical ridges and unequal interfacet processes, M11598. l Lateral view of large, broken cup with unequal processes, note right angle between aboral ligament pit and adoral part of articular facet; M11602