ii. 27, 49, 58, 79

Cuillin Hills, scenery of, i. 106; gabbro of, ii. 329, 361; acid rocks of, 391 Culots, i. 78, 88 Culm-measures, ii. 33 Cumbrae Islands, i. 368, 369, 378, 407 Cumming, J. G., ii. 22 Cycles, volcanic, i. 27, 92; ii. 116

Dacite, i. 230; ii. 185 Dakyns, Mr. J. R., i. 90, 229, 272; ii. 10 Dalmellington, volcanic rocks at, i. 333; ii. 62 Dalmeny type of dolerite and basalt, i. 418, 420 Dalradian rocks, probable crushed necks of, i. 75, 125; lavas and sills of, 121; green schists of, 124 Dalry, Ayrshire, buried volcanoes of, i. 434 Dana, J. D., ii. 189 Darwin, C., i. 27 Daubrée, A., i. 72, 404 Davies, J., i. 156, 157 Dechen, H. von, i. 46; ii. 112, 280, 333, 340, 367, 372, 381 Deformation, effects of, on volcanic rocks, i. 75, 115, 117, 119, 121, 127, 129, 162 De la Beche, H., i. 142, 143, 170, 175, 204, 205, 207, 259; ii. 9, 10, 19, 33, 95, 96, 97 Delessite, ii. 79 Denudation, influence of, on volcanoes, i. 3, 4, 8, 40, 43, 45, 46, 54, 58, 71, 73, 75, 79, 87, 100-107, 370, 433, 434, 436, 476; ii. 55, 61, 62, 179, 181, 182, 241, 245, 248, 249, 255, 257, 282, 283, 292, 316, 317, 363, 373, 407, 455 Derbyshire, toadstones of, i. 359; ii. 8 Desmarest, ii. 373 Devitrification of volcanic rocks, i. 18, 19, 78; ii. 437, 446 Devonian system, i. 257; volcanoes of, 259 Devonshire, volcanic scenery of, i. 103; Devonian volcanic rocks of, 259; Carboniferous volcanic rocks of, ii. 32; Permian volcanic rocks of, 94 Diabase, i. 151, 153 (analyses), 156, 192, 194, 204, 206, 214, 217, 235, 240, 247, 249, 273 (analyses), 278, 292, 318, 320, 330, 335, 344, 345, 351, 403; ii. 5, 136, 415 Diabase-porphyrite, i. 192, 204 Diamond found in volcanic vents, i. 62 Dick, Mr. A., jun., i. 380 Dickson, Mr. E., ii. 23 Differentiation in igneous rocks, i. 22, 27, 84, 85, 90, 91, 449;