Hostname: page-component-cd9895bd7-fscjk Total loading time: 0 Render date: 2024-12-26T04:17:25.451Z Has data issue: false hasContentIssue false

Simpson Group (Middle Ordovician) Trilobites of Oklahoma

Published online by Cambridge University Press:  22 December 2017

Abstract

The Middle Ordovician Simpson Group of southern Oklahoma consists of an exceptionally continuous record of carbonates, shales and quartz sandstones which accumulated in a shallow shelf environment. Vertical changes in the distribution of trilobite genera from these rocks can reasonably be interpreted as due to age rather than the influence of various environments or faunal provinces. The affinities of the lower Simpson trilobite faunas are with inner shelf faunas of trilobite zones M and N known from Utah and eastern Nevada and, to a lesser degree, with early Middle Ordovician faunas of Quebec and Newfoundland. Middle Simpson (McLish and Tulip Creek) Formations reflect slightly higher energy conditions and very few well-preserved trilobites. Those few genera present (for example, Pliomerops and Eorobergia) are more typical of the Chazy Group and correlatives from eastern North America. The higher Bromide Formation, also of shelf origin, displays a distinctly eastern fauna, very similar to elements found in the Chazy Group and the presumably younger Edinburg Group of the east. Although many of Cooper's (1956) Middle Ordovician correlations can be understood, the stage names proposed at that time overlap in some cases and lack proper biostratigraphic definition in others. Abandonment of these stage names is urged until description of Middle Ordovician conodont, graptolite and shelly faunas now underway is nearer completion.

Type
Research Article
Copyright
Copyright © 1974 Paleontological Society 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

References Cited

Adkison, W. L. 1972. Stratigraphy and structure of Middle and Upper Ordovician rocks in the Sedgwick basin and adjacent areas, south-central Kansas: United States Geol. Surv., Prof. Paper 702, 33p.Google Scholar
Alberstadt, L. P. and Walker, K. R. 1973. Stages of ecological succession in Lower Paleozoic Reefs of North America; (abs.) Geol. Soc. America Ann. Mtg., p. 530532.Google Scholar
Angelin, N. P. 1854. Palaeontologia Scandinavica. P. I. Crustacea Formationis Transitionis. Lipsiae.Google Scholar
Barnes, C. R. 1973. Conodont biostratigraphy and paleoecology of the Black River and Lower Trenton Groups: (abs.) N. Central Geol. Soc. America p. 296297.Google Scholar
Bassler, R. S. 1915. Bibliographic index of American Ordovician and Silurian fossils; U.S. Nat. Mus. Bull. 92, 1521 p.Google Scholar
Bergström, S. M. 1971a. Conodont biostratigraphy of the Middle and Upper Ordovician of Europe and eastern North America: Geol. Soc. America, Mem. 127, p. 83157.Google Scholar
Bergström, S. M. 1971b. Correlation of the North Atlantic Middle and Upper Ordovician conodont zonation with the graptolite succession: Memoires du Bureau de Recherches Geologiques et Minieres No. 73, p. 177187.Google Scholar
Bergström, S. M., Ethington, R. L., Jaanusson, V. 1973. On the stage subdivision of the North American lower Middle Ordovician: Age of the strata at the top of Whiterock reference sequences in Nevada: (abs.) North-Cent. Mtg., Geol. Soc. America, p. 229.Google Scholar
Berry, B. 1972. Early Ordovician bathyurid province lithofacies, biofacies, and correlation—their relationship to a proto-Atlantic Ocean: Lethaia, v. 5, no. 1, p. 6984.Google Scholar
Beyrich, E. 1845. Uber einige böhmische Trilobiten: Reimer (Berlin).Google Scholar
Billings, E. 1859. Descriptions of some new species of trilobites from the Lower and Middle Silurian rocks of Canada: Can. Nat. and Geol. v. 4, p. 367383.Google Scholar
Billings, E. 1865. Palaeozoic fossils of Canada: Geol. Surv. Canada, 426 p.Google Scholar
Bradley, J. H. 1930. Fauna of the Kimmswick Limestone of Missouri and Illinois: Walker Mus., v. II, no. 6, p. 219290.Google Scholar
Bruton, D. L. 1965. The Middle Ordovician of the Oslo region, Norway #19. The trilobite Family Odontopleuridae: Norsk Geologisk Tidsskrift, v. 45, pt. 3, p. 339356.Google Scholar
Bruton, D. L. 1966. A revision of the Swedish Ordovician Odontopleuridae (Trilobita): Bull. Geol. Inst. Univ. Uppsala, v. XVIII, 40 p.Google Scholar
Bruton, D. L. 1968. A revision of the Odontopleuridae (Trilobita) from the Palaeozoic of Bohemia: Vid.—Akad. Skr. I. M.—N. Ki. Ny. Serie. No. 25, p. 573.Google Scholar
Burmeister, H. 1843. Die Organisation der Trilobiten. Berlin.Google Scholar
Burskyi, A. Z. 1966a. Encrinuridae from the Ordovician of northern Pai Hoy and Vaigash Island: Sci. Repts., Sci. Res. Inst. Arctic Geol., U.S.S.R., (Paleont. and biostrat.), v. 11, p. 7984.Google Scholar
Burskyi, A. Z. 1966b. The family Remopleuridae from the Ordovician of northern Pai Hoy, Vaigash and southern Novaya Zemlaya: Sci. Repts., Sci. Res. Inst. Arctic Geol. U.S.S.R., (Paleont. and biostrat.), v. 12, p. 3045.Google Scholar
Burskyi, A. Z. 1966c. Raphiophoridae and Pterygometopidae from the Ordovician of northern Pai Hoy and Vaigash Island: Sci. Rept., Sci. Inst. Arctic Geol., U.S.S.R., (Paleont. and biostrat.), v. 16, p. 821.Google Scholar
Burskyi, A. Z. 1970. Early Ordovician trilobites of northern Pai Hoy, p. 96138: in Ordovician sections of Pai Hoy, Vaigash and southern Novaya Zemlaya: Sci. Res. Inst. Arctic Geol., U.S.S.R., (ed. Bondareva, V. I.) p. 138.Google Scholar
Carnes, J. B. and Bergström, S. M. 1973. On the stage subdivision of the North American lower Middle Ordovician: Biostratigraphy and correlation of the Ashby Stage: Abs. North-Central Sec. Geol. Soc. America 1973, p. 307.Google Scholar
Chugaeva, M. N. et al. 1964. Early and Middle Ordovician trilobites in the northeast U.S.S.R.: in Chugaeva, Rozman and Ivanova, Comparative biostratigraphy of Ordovician deposits in the northeast of the U.S.S.R. Acad. Sci. U.S.S.R., Geol. Inst. Moscow p. 2474.Google Scholar
Cooper, B. N. 1953. Trilobites from the lower Champlainian formations of the Appalachian Valley: Geol. Soc. America, Mem. 55, p. 169.Google Scholar
Cooper, B. N. 1961. Geological Guidebook Number 1: Grand Appalachian Excursion: Virginia Polytechnic Inst., Engineering Extension Ser., Blacksburg, Virginia, 187 p.Google Scholar
Cooper, G. A. 1930. Upper Ordovician and Lower Devonian stratigraphy and palaeontology of Percé, Quebec: part 2; new species from the Upper Ordovician of Percé: American Jour. Sci., ser. 5, v. 20, p. 385392.Google Scholar
Cooper, G. A. 1956. Chazyan and related Brachiopods, Parts I and II: Smithsonian Misc. Colln., v. 127 (in two parts), 1245 p.Google Scholar
Dapples, E. C. 1955. General lithofacies relationship of St. Peter Sandstone and Simpson Group: American Assoc. Petrol. Geol., Bull. v. 39, p. 444467.Google Scholar
Dean, W. T. 1962. The trilobites of the Caradoc Series in the Cross Fell Inlier of northern England: Bull. British Mus. (Nat. Hist.) Geol. v. 7, no. 3, p. 65134.Google Scholar
Decker, C. E. 1931. A new species of Ampyx : Jour. Paleo., v. 5, p. 153155.Google Scholar
Decker, C. E. 1941. Simpson Group of Arbuckle and Wichita Mountains of Oklahoma: American Assoc. Petrol. Geol. Bull. v. 25, p. 650667.Google Scholar
Decker, C. E., and Merritt, C. A. 1931. The stratigraphy and physical characteristics of the Simpson Group: Oklahoma Geol. Surv., Bull. no. 55, 111 p.Google Scholar
Dekay, J. E. 1824. Observations on the structure of trilobites and description of an apparently new genus: Lyc. Nat. Hist. New York, Ann. 1, p. 174189.Google Scholar
Delo, D. M. 1940. Phacopid trilobites of North America: Geol. Soc. America, Spec. Pap. 29, 135 p.Google Scholar
DeMott, L. L. 1963. Middle Ordovician trilobites of the upper Mississippi Valley: unpub. , Harvard Univ. 236 p.Google Scholar
Derby, J. R. 1973. Remarks on the age of the Everton and Smithville-Blackrock Formations of Arkansas and correlation to Oklahoma Formations: Abs. South-Central Sect. Geol. Soc. America 1973, p. 254255.Google Scholar
Eldredge, Niles. 1972. Systematics and evolution of Phacops rana (Green, 1832) and Phacops iowaensis Delo, 1935 from the Middle Devonian of North America: American Mus. Nat. Hist., Bull. v. 147, art. 2, p. 45114.Google Scholar
Esker, G. C. 1961. A new species of trilobite from the Kimmswick limestone (Ordovician) of Missouri: Jour. Paleo. v. 35, p. 12411243.Google Scholar
Esker, G. C. 1964. New Species of trilobites from the Bromide Formation of Oklahoma: Oklahoma Geol. Notes, v. 24, p. 195209.Google Scholar
Esker, G. C., and Levin, Harold. 1964. Pandaspinapyga, a new trilobite genus from the Kimmswick Limestone of Missouri: Jour. Paleo. v. 38, p. 776778.Google Scholar
Evitt, W. R. 1951. Some Middle Ordovician trilobites of the families Cheiruridae, Harpidae and Lichidae: Jour. Paleo. v. 25, p. 587616.Google Scholar
Evitt, W. R. 1953. Observations on the trilobite Ceraurus : Jour. Paleo. v. 27, no. 1, p. 3348.Google Scholar
Finks, R. M. and Toomey, D. F. 1972. Paleoecology of Chazy Reef Mounds: Guidebook 1972 New England Intercoll. Geol. Conf. p. 443472.Google Scholar
Fisher, D. W. 1954. Lower Ordovician stratigraphy of the Mohawk Valley: Geol. Soc. America, Bull., v. 65, p. 7196.CrossRefGoogle Scholar
Fisher, D. W. 1962. Correlation of the Ordovician rocks in New York State: New York State Mus., Map and Chart Ser. no. 3.Google Scholar
Foerste, A. F. 1920. The Kimmswick and Plattin Limestones of northeastern Missouri: J. Sci. Lab. Denison Univ., v. XIX, art. 12, p. 175224.Google Scholar
Frederickson, E. A. 1957. Geologic map of the Criner Hills area, Oklahoma: Oklahoma Geol. Surv., Map Gm-4. Google Scholar
Frederickson, E. A. 1964. Two Ordovician trilobites from southern Oklahoma: Oklahoma Geol. Notes. v. 24, no. 4, p. 7175.Google Scholar
Ham, W. E., et al. 1954. Geologic map and sections of the Arbuckle Mountains, Oklahoma: Oklahoma Geol. Surv., Norman, Oklahoma.Google Scholar
Ham, W. E., et al. 1955. Field conference on the geology of the Arbuckle Mountain Region: Oklahoma Geol. Surv. Guidebook, no. 3, 61 p.Google Scholar
Ham, W. E., et al. 1969. Regional Geology of the Arbuckle Mountains, Oklahoma: Oklahoma Geol. Surv. Guidebook, no. 17, 52 p.Google Scholar
Ham, W. E., et al., and Wilson, J. L. 1967. Paleozoic epeirogeny and orogeny in the Central United States: American J. Sci., v. 265, p. 332407.Google Scholar
Ham, W. E., et al., Wilson, J. L., Denison, R. E., and Merritt, C. A. 1964. Basement rocks and structural evolution of southern Oklahoma: Oklahoma Geol. Surv., Bull. 95, 302 p.Google Scholar
Harrington, H. J., and Leanza, A. F. 1957. Ordovician trilobites of Argentina: Univ. Kansas, Dept. Geol., Spec. Pub. 1, 276 p.Google Scholar
Harris, R. W. 1957. Ostracoda of the Simpson Group of Oklahoma: Oklahoma Geol. Surv., Bull. 75, 333 p.Google Scholar
Harris, R. W., and Harris, R. W. 1965. Pruitt Ranch, new member of Oil Creek (Simpson) in Criner Hills, Oklahoma: Tulsa Geol. Soc. Dig., v. 33, p. 144160.Google Scholar
Hawle, I. and Corda, A. J. C. 1847. Prodrom einer Monographie der böhmischen Trilobiten: K. Böhm. Gesell. Wiss. (Prague), Abhandl., v. 5, 176 p.Google Scholar
Hintze, L. F. 1952. Lower Ordovician trilobites from western Utah and eastern Nevada: Utah Geol. Min. Surv., Bull. 48, 1249 p.Google Scholar
Holliday, Samuel. 1942. Ordovician trilobites from Nevada: Jour. Paleont., v. 16, p. 471478.Google Scholar
Ingham, J. K. 1970. The Upper Ordovician trilobites from the Cautley and Dent Districts of Westmoreland and Yorkshire: Paleontograph. Soc. Mono. Pt. 1, 58 p.Google Scholar
Jones, T. R. and Woodward, H. 1898–99. A monograph of the British Paleozoic Phyllodopa: Palaeont. Soc., 211 p.Google Scholar
Kielan, Zofia. 1959. Upper Ordovician trilobites from Poland and some related forms from Bohemia and Scandinavia: Palaeontologia Polonica No. 11.Google Scholar
Lane, P. D. 1971. British Cheiururidae (Trilobita): Palaeontograph. Soc. Mono., 95 p.Google Scholar
Laudon, L. R. 1938. Abundant occurrence of Isotelus gigas DeKay in the South Criner Hills of Oklahoma: (abs.) Geol. Soc. America, Proc. 1937, 283 p.Google Scholar
Laudon, L. R. 1939. Unusual occurrence of Isotelus gigas DeKay in the Bromide Formation (Ordovician) of southern Oklahoma: J. Paleo., v. 13, p. 211213.Google Scholar
Loeblich, A. E. 1940. An occurrence of Isotelus gigas DeKay in the Arbuckle Mountains, Oklahoma: J. Paleo., v. 14, p. 161162.Google Scholar
Moore, R. C., (ed.) 1959. Treatise on Invertebrate Paleontology: Part O Arthropoda 1. Geol. Soc. America and Univ. Kansas Press.Google Scholar
Palmer, A. R. 1965. Biomere, a new kind of biostratigraphic unit: J. Paleo., v. 39, p. 149153.Google Scholar
Palmer, A. R. 1973. Cambrian trilobites in Atlas of Palaeobiogeography, Hallam, (ed.), Elsevier, Amsterdam, p. 311.Google Scholar
Pitcher, Max. 1964. Evolution of Chazyan (Ordovician) Reefs of Eastern United States and Canada: Bull. Can. Pet. Geol. v. 12, p. 632669.Google Scholar
Phleger, Fred B. 1936. Lichadean trilobites: J. Paleo., v. 10, p. 593615.Google Scholar
Portlock, J. E. 1843. Report on the geology of the Country of Londonderry and of parts of Tyrone and Fermanagh: Dublin and London.Google Scholar
Poulsen, Charles. 1927. II. The Cambrian, Ozarkian and Canadian faunas of northwest Greenland: Meddelelser om Grønland, v. LXX, p. 237343.Google Scholar
Raymond, P. E. 1905. Trilobite of the Chazy limestone: Ann. Carnegie Mus. v. 3, no. 2, p. 328386.Google Scholar
Raymond, P. E. 1910. Notes on Ordovician trilobites: new and old species of trilobites from the Chazy: Ann. Carnegie Mus. v. 7, p. 6080.Google Scholar
Raymond, P. E. 1916. New and old Silurian trilobites from southeastern Wisconsin, with notes on the genera of the Illaenidae: Bull. Mus. Comp. Zool. Harvard Coll., v. LX, no. 1, p. 341.Google Scholar
Raymond, P. E. 1925. Some Trilobites of the lower Middle Ordovician of eastern North America: Bull. Mus. Comp. Zool. Harvard Coll., v. LXVII, no. 1, 180 p.Google Scholar
Raymond, P. E., and Barton, D. C. 1913. A revision of the American species of Ceraurus : Bull. Mus. Comp. Zool. Harvard Coll., v. LIV, no. 20, p. 525543.Google Scholar
Reed, F. R. C. 1931. The Lower Palaeozoic trilobites of the Girvan District, Ayrshire: Supplement no. 2, Mon. Palaeontogr. Soc. 30 p.Google Scholar
Reed, F. R. C. 1905. The classification of the Phacopidae: Geol. Mag. new Ser., 5, v. 2, p. 172178.Google Scholar
Richter, R. and Richter, E. 1926. Die Trilobiten des Oberdevons: Abh. preuss. Geol. Landesanst. N.F. 99, 314 p.Google Scholar
Ross, R. J. 1951. Stratigraphy of the Garden City Formation in northeastern Utah, and its trilobite faunas: Peabody Mus. Nat. Hist. Yale Univ., Bull. 6, p. 1161.Google Scholar
Ross, R. J. 1967. Some Middle Ordovician brachiopods and trilobites from the Basin Ranges, western United States: Geol. Surv., Prof. Paper 523-D, p. D1D43.Google Scholar
Ross, R. J. 1970. Ordovician brachiopods, trilobites, and stratigraphy in eastern and central Nevada: Geol. Surv., Prof. Paper 639, 103 p.Google Scholar
Ross, R. J. 1972. Fossils from the Ordovician bioherm at Meiklejohn Peak, Nevada: Geol. Surv., Prof. Paper 685, 47 p.Google Scholar
Ross, R. J., and Ingham, J. K. 1970. Distribution of the Toquima-Table Head (Middle Ordovician Whiterock) faunal realm in the Northern Hemisphere: Geol. Soc. America, Bull. v. 81, p. 393408.Google Scholar
Ross, R. J., Ingham., J. K., and Shaw, F. C. 1972. Distribution of the Middle Ordovician Copenhagen formation and its trilobites in Nevada: U.S. Geol. Surv., Prof. Paper 749, 33 p.CrossRefGoogle Scholar
Sars, M. 1835. Über einige neue unvollständig bekannte Trilobiten: Oken Isis for 1835, 4 p.Google Scholar
Salter, J. W. 1848. In Phillips, J. and Salter, J. W. Palaeontological appendix to Prof. John Phillips Memoir on the Malvern Hills: Mem. Geol. Surv. Great Britain. v. 2, pt. 1.Google Scholar
Salter, J. W. 1864–83. A monograph of the British trilobites: Palaeontogr. Soc. Mon. 244 p.Google Scholar
Schopf, T. J. M. 1966. Conodonts of the Trenton Group in New York, southern Ontario and Quebec: New York State Mus. and Sci. Serv. Bull., 405, 105 p.Google Scholar
Schramm, M. W. 1964. Paleogeologic and quantitative lithofacies analysis, Simpson Group, Oklahoma: American Assoc. Pet. Geol., Bull. v. 48, p. 11641195.Google Scholar
Schrank, Eckart. 1972. Nileus-Arten (Trilobita) aus Geschieben des Tremadoc bis tieferen Caradoc: Ber. deutsch. Ges. geol. Wiss. A Geol. Palaeont., v. 17, no. 3, p. 351375.Google Scholar
Shaw, F. C. 1968. Early Middle Ordovician Chazy trilobites of New York: New York State Mus. and Sci. Serv., Mem. 17, 163 p.Google Scholar
Simpson, G. G. 1960. Notes on measurement of faunal similarity: Am. Jour. Sci. v. 258A, p. 300311.Google Scholar
Sinclair, G. W. 1944. Some Ordovician trilobites from Ontario: Tr. Roy. Can. Inst. v. 25, pt. 1, no. 53, p. 1520.Google Scholar
Slocum, A. W. 1913. New trilobites from the Maquoketa beds of Fayette County, Iowa: Pubs. Field Mus. (Geol.) v. 4 (3) (Pub. 171) p. 4383.Google Scholar
Slocum, A. W. 1916. Trilobites from the Maquoketa beds of Fayette County, Iowa: Iowa Geol. Surv. Ann. Rept. v. 25, p. 183250.Google Scholar
Sloss, L. L. 1972. Synchrony of Phanerozoic Sedimentary-Tectonic Events of the North American Craton and the Russian Platform: Sec. 6, 24th Int. Geol. Cong. p. 2432.Google Scholar
Sutherland, P. K., and Amsden, T. W. 1959. A reillustration of the trilobite Lonchodomas mcgeheei Decker from the Bromide Formation (Ordovician) of southern Oklahoma: Oklahoma Geol. Notes, v. 19, no. 10, p. 212219.Google Scholar
Sweet, W. C., and Bergström, S. M. 1973. Biostratigraphic potential of the Arbuckle Mountains sequence as a reference standard for the mid-continent Middle and Upper Ordovician: Abs. North-Central Sec. Geol. Soc. America 1973, p. 355.Google Scholar
Sweet, W. C., Bergström, S. M., Bergström, S. M. and Carnes, J. B. 1973. Lower Middle Ordovician biostratigraphy in the North American mid-continent: Relations between sequences in Oklahoma, the Cincinnati region, and the western Appalachians: Abs. Ann. Mtg. Geol. Soc. America, 1973, p. 832833.Google Scholar
Textoris, D. A. 1968. Petrology of supratidal, intertidal, and shallow subtidal carbonates, Black River Group, Middle Ordovician, New York, United States of America: XXIII International Geol. Cong, v. 8, p. 227248.Google Scholar
Tripp, R. P. 1954. Caradocian trilobites from mudstones at Craighead quarry, near Girvan, Ayrshire: Trans. Roy. Soc. Edinburgh, v. LXII, pt. III, no. 16, p. 655693.Google Scholar
Tripp, R. P. 1957. The classification and evolution of the Superfamily Lichacea (Trilobita): Geol. Mag, v. XCIV, no. 2, p. 104122.Google Scholar
Tripp, R. P. 1962. Trilobites from the “Confinis” Flags (Ordovician) of the Girvan District, Ayrshire: Trans. Roy. Soc. Edinburgh, v. LXV, no. 1, 40 p.Google Scholar
Tripp, R. P. 1965. Trilobites from the Albany division (Ordovician) of the Girvan District Ayrshire: Palaeontol., v. 8, pt. 4, p. 577603.Google Scholar
Tripp, R. P. 1967. Trilobites from the Upper Stinchar Limestone (Ordovician) of the Girvan District, Ayrshire: Trans. Roy. Soc. Edinburgh, v. 67, no. 3, p. 4393.Google Scholar
Ulrich, E. O. 1892. Two new Lower Silurian species of Lichas (subgenus Hoplolichas): American Geol. v. 10, p. 271272.Google Scholar
Walcott, C. D. 1886. Second contribution to the studies on the Cambrian faunas of North America: United States Geol. Surv. Bull. v. 30, 369 p.Google Scholar
Walker, K. R., and Laporte, L. F. 1970. Congruent fossil communities from Ordovician and Devonian carbonates of New York: J. Paleo., v. 44, no. 5, p. 928944.Google Scholar
Walter, O. T. 1924. Trilobites of Iowa and some related Palaeozoic forms: Ann. Rept. Iowa Geol. Surv. v. 31, p. 173351.Google Scholar
Warder, J. A. 1838. New trilobites: American Jour. Sci., v. 34, p. 377380.Google Scholar
Whittington, H. B. 1949. Dolichoharpes and the origin of the harpid fringe: American J. Sci., v. 247, p. 276285.Google Scholar
Whittington, H. B. 1950. Sixteen Ordovician genotype trilobites: J. Paleo., v. 24, no. 5, p. 531565.Google Scholar
Whittington, H. B. 1953. North American Bathyuridae and Leiostegiidae (Trilobita): J. Paleo., v. 27, no. 5, p. 664678.Google Scholar
Whittington, H. B. 1954. Ordovician trilobites from Stilliman's Fossil Mount: Geol. Soc. America, Mem. 62, p. 119149.Google Scholar
Whittington, H. B. 1956. Silicified Middle Ordovician trilobites: The Odontopleuridae: Bull. Mus. Comp. Zool. Harvard Coll., v. 114, no. 5, p. 159288.Google Scholar
Whittington, H. B. 1959. Silicified Middle Ordovician trilobites: Remopleurididae, Trinucleidae, Raphiophoridae, Endymioniidae: Bull. Mus. Comp. Zool. Harvard Coll., v. 121, no. 8, p. 373496.Google Scholar
Whittington, H. B. 1960. Cordania and other trilobites from the Lower and Middle Devonian: J. Paleo., v. 34, no. 3, p. 405420.Google Scholar
Whittington, H. B. 1961. Middle Ordovician Pliomeridae (Trilobita) from Nevada, New York, Quebec, Newfoundland: J. Paleo., v. 35, no. 5, p. 911922.Google Scholar
Whittington, H. B. 1962. The Ordovician trilobites of the Bala area, Merioneth: Palaeontograph. Soc., pt. I, 32 p.Google Scholar
Whittington, H. B. 1963. Middle Ordovician trilobites from Lower Head, western Newfoundland: Bull. Mus. Comparative Zoo. Harvard Coll., v. 129, no. 1, p. 1118.Google Scholar
Whittington, H. B. 1965a. The Ordovician Trilobites of the Bala area, Merioneth: Palaeontograph. Soc., pt. II, p. 3362.Google Scholar
Whittington, H. B. 1965b. Trilobites of the Ordovician Table Head Formation, western Newfoundland: Bull. Mus. Comp. Zool. Harvard Univ., v. 132, no. 4, p. 275442.Google Scholar
Whittington, H. B. 1966. Phylogeny and distribution of Ordovician trilobites: J. Paleo., v. 40, no. 3, p. 696737.Google Scholar
Whittington, H. B., and Evitt, W. R. 1954. Silicified Middle Ordovician Trilobites: Geol. Soc. America, Mem. 59, 137 p.Google Scholar
Whittington, H. B., and Hughes, C. P. 1972. Ordovician geography and faunal provinces deduced from trilobite distribution: Philosophical Trans. Roy. Soc. London B., Biol. Sci., v. 263, no. 850, p. 235278.Google Scholar
Young, F. P. 1943. Black River Stratigraphy and Faunas, Parts I and II: American Jour. of Sci., vol. 241 March, p. 141166 and April, p. 209–240.Google Scholar
Zen, E. A. (ed.) et al. 1968. Studies of Appalachian geology: Northern and Maritime: Wiley, New York, 475 p.Google Scholar
Zenker, J. C. 1833. Beiträge zur Naturgeschichte der Urwelt. Organische Reste (Petrefacten) aus der Altenburger Braunkohlen-Formation dem Blankenburger Quadersandstein, Jenaischen bunten Sandstein und Böhmischen Uebergangsgebirge. Jena.Google Scholar