INDEX. 



687 



Meteorites, 22 



characters of. 23 

 Meteorites and comets, common 

 minerals absent from, 29 



iron in, 27 



origin of, 23 



relations of, 36 



swarm of. 18 



velocities of. 16 

 Meteoritic gases, 95 



hypothesis of earth's origin, 13 



state, origin of, 15 



swarm, initiation of. 16 



tenuity of celestial matter 

 under. 19 

 Michelinia. 457 



lenticularis, 455 

 Michigamme formation, 186, 187 

 Michigan series, 503 

 Microdiscus speciosus, 297 

 Microsauria, 607, 608 

 Middle Cambrian, 224, 241 

 Middle Devonian, 424 



geographic changes during, 

 430 



in the northwest, 429 

 Mid-Ordovician fauna, 36s 

 Mid-Silurian fauna, 399 



foreign relations, 409 

 Milky Way, 53 

 Millsap division, 563 



limestone, 506 

 Millstone grit, 539, 562 

 Menevian group, 271 

 Minnesota, Archean of, 150 

 Mississippian amphibia, 537 



climate, 518 



fauna of Great Basin, 527 



fishes, 534 



labyrinthodonts, 538 



land life, 537 



life of, 518 



marine faunas of, 518 



period, 496, 507 



igneous activity, 507 



sharks, 535 



system, subdivisions of, 500 

 thickness of, 510 



west of Great Plains, 505 

 Missouri, lead in, 337 



series, 561 



zinc in, 337 

 Missourian formation, 542 

 Mitrocystis mitra, 359 

 Moccasin limestone, 316 

 Modes of deformation under 

 planetesimal hypothesis, 123 

 Modified hypothesis of earth's 



history, stages under, 90 

 Modiolopsis arguta, 354 

 Mohawkian system, 310 

 Molengraaff, G. A. F., cited, 636 

 Molgophis, 608 

 Molluscoidea (see Brachiopods) 



Cambrian, 284 

 Mollusks. Carboniferous. 615 



Devonian, 454."459, 465. 473 



Genevieve, 533 



Mississippian, 521, 527, 528, 

 533 



Mollusks, Ordovician. 352 



Onskany, 459 



Permian, 653 



Silurian, 405 

 Molten eon, 90 



zone, middle. 8 

 Moment of momentum of 



planets, 11 

 Mona schist, 149, 150 

 Monongahela series, 542, 557, 



558, 560 

 Monopteria longispina, 616 

 Montezuma schist, 152 

 Monticulipora, 357 



arbor ea, 358 

 Moulton. F. R., cited, 4, 10, 11, 

 17, 38, 54, 57, 62, 63, 65, 

 72 

 Mount Holly formation, 213 

 Mountain limestone, 558 

 Muensteroceras oweni, 520 

 Murchison, R. I., cited, 340 

 Murchisonia, Onondagan, 466 

 Myalina recurvirostris, 616 

 Myriopods, Carboniferous, 611 



Devonian, 495 



Naosaurus, 649 

 Narragansett Bay coal, 549 

 Nashville dome, 335 

 Nathorst, A., cited, 298 

 Naticopsis altonensis, 616 

 Nautilus family, Hamilton, 473 



Mississippian, 525 



Onondagan, 466 

 Nebulae, aggregate molecular, 42 



characteristics of, 41 



existing, 12 



free-molecular, 41 



luminescence, 59 



origin of, 21 



planetesimal, 48 



spiral form dominant, 43 

 Nebular hypothesis, 4 



difficulties of, 84, 86 



earth's history under, 90 



modification of, 88 

 Negaunee formation, 150, 176, 



179, 180 

 Neontaric series, 370 

 Neotremata, 356 

 Neumavr, M., cited, 444, 446 

 Neuropteris, 595. 602 



angustifolia, 593 



auriculata, 593 



decipiens, 594 



valida, 645 



vermicularis, 593 

 New Brunswick, Ordovician of, 



336 

 New Red Sandstone, 628 

 New York, map of western, 394 

 Newberry, J. S., cited, 461, 534, 



535. 566, 614 

 Newcomb, S., cited. 16 

 Newman limestone, 502. 559 

 Niagara fauna, 389 



formation, 377 



series, 370, 375 

 Nickles, J. M., cited, 310 



Noeggerathiopsis hislop, 645 

 Normal faulting, 235 



origin of, 131, 132 

 Northern Interior c^ul-field, 548 

 Norton, W. H., cited, 424 

 Norton formation, 559 

 Nova Scotia, Clinton formation 

 of, 375 



Ordovician, 336 

 Nova Scotia-New Brunswick coal- 

 field. 548 

 Novae, 41 

 Nuclear growth, 78 



stage of earth's history, 92 

 Nucleocrinus verneuili, 463 



Obolella gemma, 285 



poiita, 299, 300 

 Ocean basins, origin of, 106-tn 

 Oceanic circulation, Permian, 

 669 



era, 83 

 Odontocephalus aegeria, 463 

 Odontopleura crosotus, 349 

 Odontopteris, 595 



cornuta, 593 

 Oenonites rostratus, 363 

 Ogishkee conglomerate, 150, i\sJo 

 O'Hara, C. C, cited, 420, 500 

 Old Red Sandstone, 444 

 Oldham, R. D., cited, 590, 635 

 Oldhamia, 279 



antiqua, 279 

 Olenellus, 296, 300 



Cambrian, 241 



fauna, 240, 296 



gilberti, 296, 297 

 Olenoides curticei, 298, 299 

 Olenus fauna, 241 

 Oligoporus, 530 



mutatus, 525 

 Oliver, cited, 595 

 Oncoceras pandion, 352 

 Oneida conglomerate, 370 



formation, 371 

 Onondagan annelids, 467 



arthrodirans, 461 



brachiopods, 464 



bryozoans, 467 



cephalopods, 465 



corals, 463 



crinoids, 464 



crossopterygians, 461 



fauna, 452, 460, 462 



fish. 460 



formation, 418, 424 



ganoids, 461 



protozoans, 467 



sharks, 461 



sponges, 467 



trilobites, 467 

 Ontaric (see Silurian) 

 Onychodus, 463 

 Ophileta complanata, 353 



primordialis, 299 

 Ordovician annelids, 361, 363 



Appalachian sections of, 315 



brachiopods, 355. 356 



bryozoans, 357 



cephalopods , 3^2 



