zone of, [40].
Flow texture, of extrusive rocks, [33].
Fluviatile deposits, [35].
Fluvio-glacial deposits, [31].
Fluxion texture, of extrusive rocks, [33].
Folds, analysis of, [54];
comparison of shapes of, [44];
mutilated, restoration of, [45];
pitching, [43];
secondary, [44];