New determinations of carbon dioxide in water of the Gulf of Mexico--Geology of northeastern Montana--Deposits of Claiborne and Jackson age in Georgia--The structure and stratigraphy of Gravina and Revillagigedo Islands, Alaska--Two lamprophyre dikes near Santaquin and Mount Nebo, Utah--Relations of late Paleozoic and early Mesozoic formations of southwestern Montana and adjacent parts of Wyoming--New graphic method of determining the depth and thickness of strata and the projection of the dip--A contribution to the geology of northeastern Texas and southern Oklahoma--Some American Cretaceous fish scales, with notes on the classification and distribution of Cretaceous fishes.