valley of, 209.

Ampere, M., on electric currents in the earth, 543.

Amphitherium, in oolite of Stonesfleld, 138.

Andes, changes of level in, 762.
----, height of perpetual snow on, 112.
----, volcanoes of, 346.
----, sudden upheaval of, 170.
----, signs of lateral pressure in, 171.

Andesite, rock described, 347.

Angiospermous plants wanting in older rocks, 133.

Animals, extinction of, 700.
----, quantity of food required by large, 82.
----, Lamarck on production of new organs in, 568.
----, imported into America have ran wild, 585, 685.
----, aptitude of some kinds to domestication, 593, 598.
----, hereditary instincts of, 593.
----, domestic qualities of, 592, 595.
----, their acquired habits rarely transmissible, 595, 600.
----, changes in brain of foetus in, 609.
----, plants diffused by, 623.
----, their geographical distribution, 76, 77.
----, migrations of, 685.
----, causes which determine the stations of, 669, 676.
----, influence of man on their distribution, 682.
----, fossil, in peat caves, &c., 722, 725, 730, 732, 749, 752.

Anio, R., flood of the, 212.
----, travertin formed by, 244.

Anoplotherium, fossil of Isle of Wight, 142.

Antarctic circle, area still unexplored, 99.

Antwerp, sunk region near, 327.

Apennines, their relative age, 119, 124.

Aphides, account of a shower of, 656.
----, their multiplication, 673.

Aqueous causes, supposed former intensity of, 153.
----, their action described, 198.

Aqueous lavas, description of, 374, 385, 728.

Arabian Gulf filling with coral, 776.

Arabian writers, 17.

Arago, M., on influence of forests on climate, 715.
----, on solar radiation, 127.
----, on level of Mediterranean and Red Sea, 294.
----, on formation of ground ice, 221.

Araucanian tradition of a flood, 499.

Araucaria, fir in coal, 88.

Arbroath, houses, &c., swept away by sea at, 302.

Archiac, M., 257.

Arctic fauna extended farther south than now, 125.

Arduino, memoirs of, 41.
----, on submarine volcanoes, 41, 71.

Areas of elevation and subsidence proved by coral islands, 792.

Aristarchus, 212.

Aristotle, opinions of, 12.
----, on spontaneous generation, 22.
----, on deluge of Deucalion, 356.

Arkansas, R., 264.
----, floods of, 270.

Arso, volcanic eruption of, in Ischia, 365.

Artesian well at Paris, temperature of water,