INDEX 



Abrasion by wind, 22 

 Acadian epoch, 344, 346 

 Accidents to streams, 101-107 

 Acidic rocks, 252 

 Acondylacanthus gracilis, 433 

 Acrocrinus amphora, 436 

 Acrotreta gemma, 360 

 Actaeon shilohensis, 597 

 Actinocrinus lobatus, 434 

 Actinocrinus senectus, 433 

 Attinolite, 255 

 Actinoptcria textilis, 414 

 Adams, V. D., cited, 240 

 Adirondacks, Proterozoic rocks of, 

 Adjustment of streams, 97, 98 

 Africa, Cretaceous in, 544 



Devonian in, 412 



Miocene of, 500 



IVnnsylvanian in, 457 



Permian in, 474 



Triassic in, 493 

 Aftonian epoch, 633 

 Agassiz, A., cited, 167 

 Agassizocrinus dactyliformis, 436 

 Agates, 254, 286 

 Age of earth, 168 

 Agglomerate, 250, 258, 263 

 Au'uradation by sti earns, 107 

 Augustus interstrictus, 359 

 Alabaster, 257 



Algonkian. See Proterozoic. 

 Allegheny series, 443 

 Alluvial cones, 108, 109 



deposits, 108, 660 



fans, 109, no 



plains, in 



terraces, 119 

 Alpine glaciers, 127 

 Amazonstone, 254 

 Amber, 577 

 Amberleya dilleri, 531 

 Amethyst, 254 

 Ammonites, 499 



Jurassic, 509 

 Amphibians, Eocene, 572 



Pennsylvanian, 464 



340 



Amphibians continued 



Permian, 477 



rise of, 464 



Triassic, 494 

 Amphibole, 253, 255 

 Amygdaloid, 259 

 Anatina austinensjs, 530 

 Anchippus, 579, 592 

 Anchisaurus colurus, 495 

 Anderson, R., cited, 583 

 Angiosperms, Comanchean, 528 



place of origin, 528 

 Animals, classification of, 686 

 Animikean, 331 

 Annelids. See worms. 

 Annularia sphenophylloides, 461 

 Anomalina ammonoides, 572 

 Anomalocrinus incurvus, 384 

 Antecedent drainage, 105 

 Anthracite coal, 453 

 Anthracite coal field, 443 

 Anthrapalaemon gracilis, 466 

 Anticlinal fold, 274 

 Anticlinoria, 220, 277 

 Antiquity of man, 670-676 

 Apennines, Pliocene in, 608 

 Aperiodic movements, 219 

 Aphanite, 248, 259, 262 

 Aphorrhais prolabiata, 554 

 Appalachian coal field, 443 

 Appalachian drainage, 105 

 Appalachian Mountains, age of, 475 

 Aqueous metamorphism, 286 

 Arabellites cornutus, 386 



ovalis, 386 



Arapahoe formation, 539 

 Area staminea, 595 



tehamaensis, 531 

 Archieopteris bochsiana, 460 

 Ai chaeopteryx macrura, 519 

 Archean, bearing on origin of earth, 323 



delimitations, 317 



distribution of, 320, 322 



general characteristics, 317 



granites, 318 



origin of, 318, 320 



687 



