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];