undet. Bivalvia

Geological context: Late Cretaceous, Fox Hills Fm, Trail City Mbr. Collection locality: conc., high in LNAZ, probably Drepanochilus concs. layer, SW-facing bluffs of SE-trending spur that joins terrace to S and SE, 2 mi WNW of Little Eagle, Corson County, South Dakota, USA. Collected by Karl M. Waage, 1962. IP number 315087; lot count 1; taphonomy=concretion; accn=IPA.07048; associatedwith=on same slab: IP.315087,IP.315088,IP.315089,IP.315092,IP.315093,IP.315094,IP.315095,IP.315096,IP.315097,IP.315099,IP.315102,IP.315104,IP.315105,IP.315106,IP.315107,IP.315109,IP.315111,IP.315112,IP.315113,IP.315114,IP.315115,IP.315116,IP.315117,IP.315118,IP.315119,IP.315120,IP.315126,IP.315128,IP.315129,IP.315130,IP.315131,IP.315132,IP.315133,IP.315136,IP.315137,IP.315138,IP.315139,IP.315140,IP.315098,IP.315127,IP.315090,IP.315091,IP.315100,IP.315101,IP.315103,IP.315108,IP.315110,IP.315121,IP.315122,IP.315123,IP.315124,IP.315125,IP.315134,IP.315135.