
INDEX. 
Anthracitie (Silurian) shales, 661, 671 
Anthracomya, 732 
Anthracoptera, 732 
Anthracosaurus, 733° 
Anthracosia, 7 20, 732 
Anthracotherium, 856, 869; asa type facil 
616 
Anthrapalzmon, 724, 725* 
Anticline, 517, 914 
Antilope, 864, 872 
Antiparos, grotto of, 355 
Antwerp, Black Crag of, 865, 876 
Anvyersien (Pliocene), 876 
_ Apatite, 84; detection of, 193 
Apatornis, 812 
Apatosaurus, 801 
Apes, early forms of, 80+, 868, 872 
Aphanite, 143 
Aphanitic structure, 88 
Apiocrinus, 773 
Aporrhais, 806, 844 
Appalachian coal-field, 517; a 
flexures of, 914 
Aptien, 824 
Aptychopsis, 664 
Aptychus, 800 
Aptychus Beds, 800, 830 
Aqueous rocks, 108 
Aquitanian stage, 860, 861 
-Arachnids, early forms of, 724, 732 
Aragonite, 83, 106; converted to calcite by 
high temperature, 352; occurrence of in 
invertebrates, 608 
Aral, Sea of, 397 
Aralea, 849 
Aralo-Caspian depression, 235, 236, 32, 
396, 397, 398 
Ararat, yoleanic breccia of, 206; structure 
of, 243; fulgurites of, 319 
Araucaria, 772 
Araucarioxylon, 730, 768 
Araucarites, 757, 792 
Arbroath Flags, 711, 713 
Arca, 753, 793, 818, 847, 860, 862*, 896 
Arcestes, 763 
Archean rocks, 588, 637 
Archxocidaris, 722 
Archxocyathus, 663 _ 
Archxopteryx, 781, 783* 
Archegosaurus, 757 
Archimedes, 750 
Archimylacris, 732 
Archiulus, 732 
Arctic plants in glacial deposits, 88+ 
Arctic regions, ancient floras of, 15, 868 ; 
uprise of land in, 279, 280; effects of 
frost in, 401; ice of, 404, 416, 417, 424, 
425; ancient luxuriant floras of, 15, 868 ; 
Old Red Sandstone of, 717; Cretaceous, 
831, 832; Tertiary, 868 
Arctocephalus, 881 
_Artocyon, 840 
- Ardoise, 121 
_Ardwell Group, 671 
Arenicolites, 650* 
Arenig Group, 667 
Argillaceous, 90 
Argillaceous-schist, 121 
Argillite, 121 
Argillornis, 840 
Argovien, 797 
Arietites (Ammonites), 786, 787* 
Arionellus, 659 
Aristozoe, 664 
Arkose, 159 
Armorican Sandstone, 691 
Artesian wells, 346 
Arthrophycus, 662 
Arthropitus, 733, 752 
Arthrostigma, 708 
Arve, slope of, 363 
Arvicola (vole), 875 
Arvonian rocks, 643 
Asaphus, 655, 664, 665* 
Ascension, bombs of, 206 
Ascoceras, 666 
Ash-tree, early forms of, 829 
Ashdown Sand, 817 
Asia, never united to Australia, 35; aver- 
age height of, 56; coast-line of, 41; 
daily range of temperature in Central, 
319 ; dust drift of, 322; sandy deserts 
of, 395 - deep rock-weathering in, 338 ; 
tundras of, 397 
, Archean gneiss of, 646; 
rocks, 692; Carboniferous, 749; Trias, 
770; Jurassic, 801; Cretaceous, 831; 
Tertiary, 852, 869; Post-Tertiary, 901 
Asphalt, 173; in eruptive rocks, 576 
Aspidoceras (Ammonites), 784, 793* 
Aspidorhynchus, 800 
Asplenites, 767 
Asplenium, 803, 838 
Assise, defined, 635 
Astarte, 774, 778*, 819, S44, 855, 873, 
896 
Astartian Group, 795, 797 
Asteracanthus, 794 
Asterolepis, 710 
Asterophyllites, 726, 72 
Astian (Pliocene), 878 
Astrxospongia, 663 
Astrocenia, 789 
Astronomy and Geology, 6 
Astropecten, 696, 797 
Astylospongia, 663 
Atchafalaya, rafts of the, 368 
Atherfield Clay, 818 
Atlantic Ocean, mean depth of, 32; vol- 
canic detritus on bottom of, 254, 450; 
tides of, 418; distribution of tempera- 
ture in, 420; height of waves in, 422; 
warm and cold currents of, 426; gravel 
on bottom of, 435; floating ice of, 436 
Atlantosaurus, 779 
Atmosphere, currents of, 13; height of, 
30; composition of, 30; pressure of, 
317; influence of pressure of on volcanic 

Silurian 
S74", 
Lb ~ 
S*enioe 
