INDEX. 



VOLUME II. 



Abbot, C. G., cited, 677 

 Abysmal life, Devonian, 479 

 Acadian series, 219, 241 

 Acanthaspis, 463 

 Acanthodians, Devonian, 489 

 Accretion, planetesimai, mode 



of, 64 

 Acidaspids, Onondagan, 467 

 Acondylacanthus gracilis, 521 

 Acrocrinus amphora, 532 

 Acrotreta gemma, 285, 299 

 Actinocrinidae, 520 

 Actinocrinus, 522 

 lobatus, 525 

 senectus, 520 

 Actinopteria textiles, 455 

 Actinopterygians, Devonian, 489 

 Adams, F. D., cited, 145. 204 

 Adams, G. I., cited, 562 

 Adiantes, 595 

 Adirondack region, Proterozoic 



of, 205 

 Agassizocrinus dactyhf ormis, 532 

 Agawa formation, 180 

 Agelacrinidae, 530 

 Agelacnnus, 470 

 Agitation and C0 2 of ocean, 667 

 Agnatha, 482 

 Agnostus interstrictus, 298, 299 



obtusilobus, 299 

 Agraulus, 299 

 Air-breathing life, oldest aquatic, 



529 

 Aistopoda, 607, 608 

 Ajibik quartzite, 150, 179, 180 

 Albany series (Texas), 563 

 Alethopteris, Mississippian, 357 



Pennsylvanian, 595 

 Algonkian, definition of, 162 



(see Proterozoic) 

 Allegheny series, 542, 557, 558, 



560 

 Allen, J., cited, 595, 596 

 Allorisima subcuneata, 616 

 Amalitzky, V., cited, 630, 646, 



650 

 American graptolites, 345 

 Ammonites, Permian, 653 

 Amphibians, Carboniferous, 606 

 Mississippian, 537 

 Permian, 646 

 Anamorphism, 142 

 Ancestral sun, 51 

 Aneimites, 595 



Angstrom, K., cited, 671, 672 

 Animikean system, 183-191 



composition of, 183 



deformation and erosion of, 

 185 



distribution of, 18b 



igneous rocks of, 184 



Menominee region, 187 



Mesabi region, 189 



metamorphism of, 185 



sections of, 186 



thickness of, 184 



Vermilion region, 190 

 Annelids, Devonian, 467 



Ordovician, 361, 363 



Upper Cambrian, 299 

 Annulana longifoua, 594 



Mississippian. 537 



spenophylloides, 594. 597 

 Anomalocrinus incurvus, 359 

 Anomodontia, 649, 651 

 Anoplotheca flabelhtes, 459 

 Anthozoa, Cambrian, 286 

 Anthracite coal, origin of, 577 

 Anthrapalaemon gracilis, 611 

 Anticosti series, 275 

 Aparchites minutissimus, 351 

 Appalachian coal-field, 546 



mountains, crustal shortening 

 in, 125 



sections of Ordovician, 315 

 Arabellites ovahs, 363 



cornutus, 363 

 Arachnoids, Devonian, 495 

 Araucarioxylon, 601 

 Archaeocyathus rensselaericus. 

 287 



minganensis, 363 

 Archaeopteris bochsiana, 593 



Mississippian, 537 

 Archean, 133— 161 



bearing on origin of earth, 

 155 



composition of, 140—143 



defined, 138 



delimitations of, 138, 160 



distribution of, 145 



early views concerning, 156 



European, 158, 159 



general characters of, 140 



intrusions in, 141, 142, 143, 

 154 



map of, 147 



metamorphism of, 144 



Archean, origin of, 140-145, 154 



and planetesimal hypothesis, 

 137 



structure of. 130, 131, 153 

 Archeocalamites, Devonian, 597 

 Archeozoic diastropnism, 144 



eon, 83 

 Archeozoic era, 133 



duration of, 160 



life of, 159 

 Archimedes, 531 



limestone, 562 



swallovanus, 532 

 Archinacella cingulata, 35;., 

 Arenicolites woodi, 285 

 Arenig beds, 342 

 Argentina, Cambrian fossils of 



300 

 Aridity, Salina epoch, 388 

 Aristozoae rotundata, 283 

 Arkansas, Manganese ore of, 377 

 Armoncan mountains, 589 

 Arrhenius, S.. cited, 671, 672 

 Arthroacantha, 470 



punctobrachiata, 471 

 Arthrodirans, Devonian, 461, 469 

 Arthrolycosa antiqua, 611 

 Arthropoda, Cambrian, 280 



Devonian, 490 



Permian, 652 

 Artisia, 601 



Aschkinass, E., cited, 671 

 Ashley, G. H., cited, 548 (and 



Blatchley), 424, 620 

 Astraeospongia meniscus, 403,408 

 Astral eon, 83, 90 

 Astrophyllites, 602 



Mississippian, 537 

 •Astylospongia, 408 



praemorsa, 403 

 Athyris, 615 



hannibalensis, 521 



lamellosa, 525 



spiriferoides, 521 

 Atmosphere, changes in effected 

 by life, 115 



changes in Permian period, 660 



nature of earliest, 95 



origin of, 93 

 Atmosphereless stage of earth, 92 

 Atmospheric carbonic acid gas, 

 662 



difficulties of nebular hypoth- 

 esis, 86 



679 



