INDEX* acutisulcata, Syntrophinella, 24, 124-125; PI. Big Spring anticline, 15, 16 IS, figs. 8, 10-19 Big Spring Station member, 14, 15 aff. anomalum, Clitendoceras, 135 Biotite, 34 Albite, 34 Black, Maurice, 36, 39 Algal limestone Black Rock formation, 27, 32 conditions of deposition of, 48 Blackford formation, 32 description of, 36-39 Brachiopoda, 112-127 distribution of, 36 Bradley, W. H., 38 origin of, 36-39 Brainerd, Ezra, 18 stromatolite types in, 36-39 Bridge, Josiah, 25, 30 alticostellata, Tritoechia, 118; PI. 13, figs. bridgei, Finkelnburgia, 20, 113; PI. 12, figs. 27, 30-36 18-24 alturensis, Lecanospira, 130 Broedel, C. H., 9 annulata?, Archaeoscyphia, 25, 26, 110-111; Butts, Charles, 28 PI. 9, figs. 1-4 anomalum, Clitendoceras, 135 Calcarenite, 19, 31, 38, 40, 47 anomalum, Ellesmeroceras (Metaellesmero- Calciferous sandrock, 18 ceras), 20 Calcilutite, 39 Anthozoa, 111-112 Calliglypha, 123 Antietam sandstone, 5 Cambro-Ordovician boundary, 16 Archaeocyathus minganensis, 110 capuliformis, Ceratopea, 25, 26, 127: PI. 11, Archaeoscyphia, 25, 26, 110 figs. 27, 28, 32, 33 annulata?, 25, 26, 110-111; PI. 9, figs. 1-4 cariniferum, Mcqueenoceras, 135 fauna, 25, 26 Cassin minganensis, 110 fauna, 18 zone, 25, 26, 38 strata, 27 armanda, Finkelnburgia, 113, 114 cassina, Hormotoma, 129 Arthropoda, 135-138 cassina, Murchisonia, 130 Axemann formation, 7 Cephalopoda, 135 Ceratopea Barnes, V. E„ 41, 46, 47 capuliformis, 25, 26, 127; PI. 11, figs. 27, Bassler, R. S., 5, 15, 22, 26, 45 28, 32, 33 Bathyurus conicus, 136 cf. pygmaea, 128; PI. 11, figs. 29-31 Beekmantown n. sp., 25, 127-128; PI. 11, figs. 24-26 history of sedimentation, 48 pygmaea, 27, 128 use of the term, 18 sp., 134; PI. 12, figs. 3, 6, 12 bella, Polytoechia, 27, 117 zone, 5 bellatula, Finkelnburgia, 20, 113 cf. cassina, Hormotomaf, 25, 27, 129-130; Bellefonte dolomite, 7, 27, 32 PI. 11, figs. 16, 17 Beliefontia cf. confusa, Hormotoma?, 25, 129; PI. 11, chamberlaini, 136 fig. 18 collieana, 20, 135-136; PI. 10, figs. 4, 5, cf. minor, Syntrophopsis, 25, 126; PI. 15, 7-10 figs. 34-36 fauna, 19, 20 cf. Ophileta, 24 nonius, 136 cf. pygmaea, Ceratopea, 128; PI. 11, figs. 29- biconcava, Lecanospira, 130 31 •Figures in boldface type indicate detailed description or discussion. 155 Downloaded from http://pubs.geoscienceworld.org/books/book/chapter-pdf/955652/mem68-bm.pdf by guest on 25 September 2021 156 BEEKMANTOWN GROUP OF MARYLAND cf. salteri, Lecanospira, 24, 132; PI. 12, fig. distribution, 14 1 lithologic character, 14 cf. tubulata, Tritoechia, 120-121; PI. 14, figs. name, 14 13-16 stratigraphie position of arenaceous zones cf. woosteri, Symphysurina, 137; PL 11, figs. in, 15 1, 2 thickness, 16 chamberlaini, Bellefontia, 136 upper contact, 15-16 Chambersburg limestone, 9, 16 Conococheague syncline, 8, 9, 10, 17, 21, 28 Charlton anticline, IS convexus, Obolus?, 20, 112-113; PL 12, figs. Chazy limestone, 18, 32 13-17 Chert Cooper, B. N., 32 cauliflower, 5 Cooper, G. A., 20, 32 cryptozoon, 21, 45 cooperi, Syntrophinella, 24, 125; PL 15, figs. irregular, 21, 28, 40, 43-44 20-28 nodular, 21, 40, 44-45 Copper Ridge dolomite, 38 Chlorite, 34 Coreanoceras, 25 Cincinnati arch, 47 costellatum, Diparelasma, 115 Clarke, J. M., 18 Cotter formation, 27 Clarkellidae, 124-126 Crustacea, 138 Classification Crustal shortening, 1, 12-13 lithologic, 33-45 Cryptozoon chert paleontologic, 109 description of, 45 Cleavage, 8, 10 distribution of, 45 Clelandia, 16, 20 origin of, 45 Clelandoceras, 27 zone, 20, 21, 24 sp., 25, 135 Cryptozoon steeli, 45 Clitambonacea, 116-121 zone, 5 Clitendoceras, 24, 25, 26 Cryptozoon stromatolites anomalum, 135 description of, 38-39 aff. anomalum, 135 distribution of, 39 Cloos, Ernst, 4, 6, 8, 9, 10, 11, 12, 15 Cullison, J. S., 27 Cloud, P. E., Jr., 36, 38, 41, 46, 47 curvirostris, Tritoechia, 117, 118-119; Pl. 14, cloudi, Lichenaria, 26, 111-112; PL 10, figs. figs. 1-12 1,6 Cushing, H. P., 18 Coelenterata, 111-112 collieana, Bellefontia, 20, 135-136; Pl. 10, Dakeoceras? sp., 20 figs. 4, 5, 7-10 deckeri, Syntrophinella, 125 collieana, Hemigyraspis, 135 delicatula, Tetralobula, 122 compacta, Lecanospira, 131 delicatula, Tritoechia, 27, 118 compacta, Ophileta, 131 Deposition compacta?, Lecanospira, 24, 131-132; PL 12, conditions of, 47-48 figs. 2, 4, 5 environment of, 45-47 concentrica, Doloresella, 25, 123; PL 14, figs. history of, 48 37-45 source of sediments, 47 conferta, Lecanospira, 130 depressum, Retroclitendoceras, 135 confusa, Murchisonia?, 129 Diaphelasma, 24, 123 Conglomerate, flat-pebble, 14, 15, 19 oklahomense, 124 conicus, Bathyurus, 136 pennsylvanicum, 24, 26, 115, 124; Pl. 15, Conocochcaguc formation figs. 1-7, 9 age, 16 Diparelasma, 25, 27 * Figures in boldface type indicate detailed description or discussion. Downloaded from http://pubs.geoscienceworld.org/books/book/chapter-pdf/955652/mem68-bm.pdf by guest on 25 September 2021 INDEX 157 costellatum, 115 Foltz anticlinorium, 8 fauna, 25, 27 Fossils marylandicum, 115; Pl. 13, figs. 13-19 abundance of, 109 silicum, 116 classification of, 109 subquadratum, 115-116; PL 13, figs. 6-12 distortion of, 109 Dolomite nature of preservation of, 109 laminated, 40-41 repositories for, 110 member of Rockdale Run formation, 22 stratigraphie range of, 109-110 mottled, 40 Franconia equivalent in Conococheague for- Dolomitization, 22, 24, 30, 35, 40 mation, 16 stages of, 43 time of, 43 Garden City formation, 21 Doloresella, 25, 122-123 Gasconade concéntrica, 25, 123; Pl. 14, figs. 37-45 dolomite, 1, 25 Dresbach equivalent in Conococheague for- equivalent, 26 mation, 16 fauna, 20, 25 Gasconadia putilla, 20, 128-129; Pl. 11, figs. Ecculiomphalus, 20, 24 11-15 sp., 128; PI. 11, fig. 23 Gastropoda, 127-135 Eccyliomphalus, 20 Geiger, H. R., 5 Echinodermata, 112 genalatus, Hystricurus, 136 El Paso limestone, 26, 27 Genesis of lithologies, 33-48 Elbrook formation, 14 Geologic sections, 49-100 elegantula, Orospira, 27, 134 Ginsberg, R. N., 35, 43, 46 Ellesmeroceras (Metaellesmeroceras) globosa, piectotrophia, 121-122; PL 14, figs. anomalum, 20 17-27 Environment of deposition, 45-47 Gorman Escharendo ceras, 24, 25 equivalent of El Paso limestone, 26 simplex, 135 formation, 26 sp., 135 gracile, Platysiphon, 135 gracilis, Murchisonia, 129 Faulting, 8-10 gymnosolenid stromatolites, 14, 15-16, 19 Feldspar, 34 description of, 36-38 Finkelnburgia, 24, 25 distribution of, 38 armanda, 113, 114 bellatula, 20, 113 Hastings Creek formation, 26 bridgei, 20, 113; PI. 12, figs. 18-24 Hatch, F. H., 36 sp., 25 Helicotoma uniangulata, 20 stonehengensis, 20, 113-114; PI. 12, figs. Hemigyraspis collieana, 135 25-32 Hintze, L. F., 21 virginica, 24, 26, 114-115; PL 13, figs. 1-5 Honeycut formation, 26 wemplei, 113 Hormotoma, 129 Finkelnburgia? sp., 16 Hormotoma? Finkelnburgiidae, 113-116 cf. H. cassina, 25, 27, 129-130; Pl. 11, figs. Fisher, D. W., 18, 47 16, 17 flectimembrus, Hystricurus, 137 cf. H. confusa, 25, 129; Pl. 11, fig. 18 Flexure folding, 1, 12 Huenellidae, 121-122 Flowage, eifect of on stratigraphie thickness, Hystricurus, 20, 24, 136 10-12 flectimembrus, 137 Flower, R. H„ 7, 26 genalatus, 136 * Figures in boldface type indicate detailed description or discussion. Downloaded from http://pubs.geoscienceworld.org/books/book/chapter-pdf/955652/mem68-bm.pdf by guest on 25 September 2021 158 BEEKMANTOWN GROUP OF MARYLAND Hystricurus (cont'd) Lesueurilla, 27, 132 paragenalatus, 136 Lesueurilla?, 25 s. 1., 26,136 sp., 132; PI. 11, fig. 19 sp. 20, 136-137; PI. 11, fig. 4 Lichenaria, 24 Hystricurus? sp., 137; PI. 11, fig. 3 cloudi, 26, 111-112; PI. 10, figs. 1, 6 simplex, 26, 112 Illite-group minerals, 34 Limestone Imbricatia, 123 algal, 36-39 incurva, Tritoechia, 118 laminated, 39 Irregular chert laminated dolomitic, 41-42 description of, 43-44 mechanical, 33-35 distribution of, 44 mottled dolomitic, 42-43 origin of, 44 oolitic, 35-36 structureless, 39-40 Jeiferson City equivalent of El Paso lime- Lithistida, 110 stone, 26 Lithologies, classification and genesis of, 33- 48 Keith, Arthur, 5 Lobosiphon, 25 Kindblade formation, 27 Localities, fossil, 100-108 Long, M. B„ 16, 34 lamellata, Stichotrophia, 126 Longview formation, 7, 26 Laminated dolomite Lower Ordovician-Middle Ordovician bound- conditions of deposition of, 48 ary, 32 description of, 40-41 Lytospira sp., 20, 132-133; PI. 11, figs. 20-22 distribution of, 41 origin of, 41 Macluritella, 24 Laminated dolomitic limestone marylandica, 24, 133; PI. 11, figs. 6-8, 10 conditions of deposition of, 48 sp., 133-134; PI. 11, fig. 9 description of, 41-42 stantoni, 133 distribution of, 42 Marmor stage, 32 origin of, 42 Martinsburg shale, 4, 5, 8, 9 Laminated limestone marylandica, Macluritella, 24, 133; PI. 11, conditions of deposition of, 48 figs. 6-8, 10 description of, 39 marylandicum, Diparelasma, 115; PL 13, distribution of, 39 figs. 13-19 origin of, 39 marylandicum, Oneotoceras?, 20 Lecanospira, 24, 25, 130-131 Massanutten synclinorium, 8, 17 alturensis, 130 Mcqueenoceras, 24, 25, 26 biconcava, 130 cariniferum, 135 cf. L. salteri, 24, 132; PI. 12, fig. 1 Mechanical limestone compacta, 130, 131 conditions of deposition of, 48 compacta?, 24, 131-132; Pl. 12, figs. 2, description of, 33-35 5 distribution of, 33 conferta, 130 origin of, 35 fauna, 24 Microcline, 34 nerine, 130 minganensis, Archaeocyathus, 110 salteri, 130, 132 minganensis, Archaeoscyphia, 110 sigmoidea, 130 minor, Syntrophopsis, 27, 126 sp., 132 mohawkensis, Murchisonia, 128, 129; PL 11, zone, 14, 25, 26, 35, 45, 131 fig. 13 * Figures in boldface type indicate detailed description or discussion. Downloaded from http://pubs.geoscienceworld.org/books/book/chapter-pdf/955652/mem68-bm.pdf by guest on 25 September 2021 INDEX 159 Mollusca, 127-135 Orthacea, 113-116 Mons formation, 21 Orthoclase, 34 Moore, E. S., 28 Mottled dolomite Palaeostrophiinae, 121-122 description of, 40 Paleogeography, 45-48 distribution of, 40 Paleontology, systematic, 109-138 origin of, 40 paragenalatus, Hystricurus, 136 Mottled dolomitic limestone Parahystricurus, 136 description of, 42-43 Pelmatozoa, 112 distribution of, 42 pennsylvanica, Tritoechia, 27, 118 origin of, 42-43 pennsylvanicum, Diaphelasma, 24, 26, 115, Murchisonia 124; PL 15, figs.