A fine complete test showing the pore pairs well. A typical conical form from above the sponge bed at the zonal base. It is characteristic of the topmost Uintacrinus Zone to the top of the Marsupites Zone at which horizon the apical disk has become markedly extended and somewhat flattened, with the genital plates rather swollen giving a somewhat bumpy appearance. This type of extended apical disk reaches an extreme in this zone.
Size: 66 mm
Size: 66 mm