Loeblich, A. R., Tappan, H. N., 1987: Foraminiferal genera and their classification. Van Nostrand, Reinhold Co. New York 1728 pp. Plate 267, Figs. 1-4: U. Carboniferous (U. Westphalian), Magdalena Formation, Franklin Mountains, Texas, USA. 1, Axial section, x 70; 2, axial section of holotype, x 70; 3, tangential section of paratype showing early change in coiling, x 70; 4, sagittal section, X 70 (from W. J. Stewart, 1958).