Geological Magazine

altered Ammonites antlers appear åsar beds bones British Cambrian Carboniferous Chalk character Cheiruridae chlorite clay Coll collection colour compound eyes conglomerate containing Cretaceous crinoids crystals deneholes deposits described Devonian district Egypt England Eocene epidote escarpment evidence eyes fauna feet felsite felspar flints formation fossils fragments free cheeks genera genus Geol GEOLOGICAL MAGAZINE Geological Society Geological Survey geologists Glacial granite gravel Greensand grit Hill horizon illustrations inches Journ lake Limestone London Lower margin memoir mica miles mineral Miocene Museum occur Oolite original Paleozoic paper pebbles pits plates posterior present Professor quartz quartzite radial radiolarian resemblance rivers rocks sand Sandstone schists Scotland seen shales shells side siliceous Silurian slate South species specimens strata structure surface Surv Tertiary thickness trilobites Turonian unconformity upper valleys valve Wachsmuth and Springer Wales Whin Sill zone