ch. A. Conglomerate facies and contact relationships of the Upper Cretaceous upper part of the Frontier Formation and lower part of the Beaverhead Group, Lima Peaks area, southwestern Montana and southeastern Idaho / by T.S. Dyman, J.C. Haley, and W.J. Perry, Jr. -- ch. B. U-Pb ages of volcanogenic zircon from porcellanite beds in the Vaughn member of the mid-Cretaceous Blackleaf Formation, southwestern Montana / by R.E. Zartman ... [et al.] -- ch. C. Occurrences of the free-swimming Upper Cretaceous crinoids Uintacrinus and Marsupites in the western interior of the United States / by William A. Cobban.