Prosperous hill, St. Helena.
Pumice, absent at the Galapagos archipelago. -laminated.
Puy de Dome, trachyte of.
Quail island, St. Jago.
Quartz, crystals of, in beds alternating with obsidian. -crystallised in sandstone. -fusibility of. -rock, mottled from metamorphic action with earthy matter.
Red hill.
Resin-like altered scoriae.
Rio de Janeiro, gneiss of.
Robert, M., on strata of Iceland.
Rogers, Professor, on curved lines of elevation.