Permian Carboniferous Devonian Gotlandian (= Silurian or Upper Silurian) Ordovician (or Lower Silurian) Cambrian Pre-Cambrian Group INDEX (_"Ref" indicates that the name is quoted in the list of references, pp. 162-169._) Acid igneous rocks, 127, 132 Adams, F. D., 125, ref. 100 Africa, S., 148. See Cape of Good Hope and Rhodesia. Agassiz, A., 25; L., 98 _Agents minéralisateurs_, 107 Algæ, calcareous, 25 Alkaline igneous rocks, 129 Alps, 14, 16, 23, 138, 143, 162 Ammonites, 23 Amphibole-Schist, 147 Amphibolite, 148 Anderson, T., 117 Andesite, 133 Andrussow, N., 84 Antrim, Co., 46, 135 Aragonite, deposition of, 17; in shells, 22, 86 Armitage, 64 Ash, 88, 111 Assimilation in igneous rocks, 128 Atlantic and Pacific types of igneous rocks, 130 Auvergne, 112 Axmouth, 46 Bacteria, extraction of iron by, 61 Bagshot Heath, 73 Bailey, E. B., ref. 102 Banded structure, 120 Barrell, J., ref. 938 Barrois, C., 125 Barytes in sandstone, 62 Basalt, 132, 135 Basic igneous rocks, 127, 132 Batholites, 123 Bavaria, dolomites of, 32 Belemnites, 23 Black Sea, 17, 84 Bohemia, 134, 158 Bonney, T. G., ref. 96 Boulder-clay, 96 Bournes, 43 Brachiopods, 24 Branner, J. C., 140 Brazil, 88, 140 Breccia, 55 Brögger, W. C., 125, 128 Brongniart, A., 2 Bunsen, R. W., 127 Cader Idris, 143 Calcareous Tufa, 14, 16 Canada, 103, 150, 158 Cañons of Arizona, 47 Cape of Good Hope, 16, 41, 59, 63, 103, 121, 136, 156 Causses, 45, 48, 50 Cayeux, L., 39 Cephalopods, 23 Chalk, 20, 42 Chamberlin, T. C., 129 Chara-limestone, 19 Cheddar, 48 Chert, 40, 62 China-clay, 86 Christiania district, 125, 128 Christmas Island, 37 Clare, Co., 46 Clay, 78 Cleavage, 89 Close, Maxwell H., 98 Cole, G. A. J., 117, refs. 8, 75 and 101 Coleman, A. C., 103 Colonsay, 152 Columnar structure, 115 Composite gneiss, 122, 153 Cones, volcanic, 112, 133 Conglomerates, 70 Connemara marble, 36 Contact metamorphism, 144 Conybeare, W. D., 35 Coral-reefs, 25; silicification in, 40 Cordier, P. L. A., 3 Cork marble, 54 Credner, H., 125, 149 Crinoidal limestone, 24 Cross, W., ref. 59 Crush-conglomerates, 28 Crystallisation in igneous rocks, 107