Article: Tetrameric crinoid columnals from the Ordovician of Wales
S. K. Donovan
Colpodecrinus forbesi sp. nov. is founded on the evidence of unusual tetrameric crinoid columnals similar to those of C. quadrifidus Sprinkle and Kolata. The columnals of C. forbesi have quadrangular lumina, either tetrastellate or square, whereas those of C. quadrifidus are tetralobate.