The American Geologist, Nide 8

Acad American basin Beecherella boulders Cambrian cañon Carboniferous clay coal color contains correlation creek Cretaceous crust crystalline deposits described developed Devonian dorsal drift earth's east eastern edge elevation Elk lake englacial epoch erosion evidence Extinct fact fauna feet formation Fossil genus Geol Geological Survey geologists glacial gneiss Goniatites granite Graptolites gravel Hall hematite hight horizon ice-sheet indicate iron iron-ores Itasca lake Jour land layers limestone limonite mass material Mesozoic miles minerals Miocene Mississippi moraines Mountain-Ranges mountains Muir glacier Muir inlet Naples beds Nicaragua Nicollet observed occur origin paper period phenomena plain Pleistocene portion present Proc Prof region Remarks replacement ridges river rocks sand sandstone schists sediments shales shore side siderite Silurian slope species spherulites strata stratum streams striæ subglacial surface Tertiary thickness tion upper valley valve vertebrate volcanic