Hostname: page-component-848d4c4894-jbqgn Total loading time: 0 Render date: 2024-06-28T23:31:27.592Z Has data issue: false hasContentIssue false

Agnostid trilobites from the Lower Ordovician of southern Sweden

Published online by Cambridge University Press:  03 November 2011

Per Ahlberg
Affiliation:
Per Ahlberg, Department of Historical Geology and Palaeontology, University of Lund, Sölvegatan 13, S-223 62 Lund, Sweden

Abstract

Agnostid trilobites are described from the Lower Ordovician (Oelandian Series) of Öland, Östergötland, Västergötland and Närke, southern Sweden. In addition, a few agnostids are described from the Ceratopyge Limestone (upper Tremadoc) of Scania (Skåne), the southernmost province of Sweden. 24 species (of which Galbagnostus nericiensis is new), assigned to four genera, are described or discussed. Species of Geragnostus and Arthrorhachis dominate numerically. Also recorded locally are species of Galbagnostus and Leiagnostus. Most species have a markedly restricted vertical distribution, and many species appear to have a sufficiently short range to be of value in stage- and zone-level correlation. Agnostids are represented almost throughout the Lower Ordovician of southern Sweden, but they have not been recorded from the Tremadocian “Dictyonema” and Ceratopyge Shales, nor from the upper Holen Limestone (upper Kundan Stage). In the Ordovician of Baltoscandia, agnostids are largely restricted to the Central Baltoscandian Confacies Belt; they are very rare or absent in the adjacent belts to the east and in the graptolitic shales of the Scanian Confacies Belt.

Type
Research Article
Copyright
Copyright © Royal Society of Edinburgh 1992

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

Ahlberg, P. 1988a. Ocular structures in an Ordovician agnostid trilobite. LETHAIA 21, 115–20.CrossRefGoogle Scholar
Ahlberg, P. 1988b. Agnostid trilobites from the Ordovician of Jämtland, Sweden. GEOL FÖREN STOCKH FÖRH 110, 267–78.CrossRefGoogle Scholar
Ahlberg, P. 1988c. A revision of the Ordovician agnostid trilobite Leiagnostus Jaekel 1909. GEOL FÖREN STOCKH FÖRH 110, 363–70.CrossRefGoogle Scholar
Ahlberg, P. 1989a. Agnostid trilobites from the Upper Ordovician of Sweden and Bornholn, Denmark. BULL GEOL SOC DENM 37, 213–26.CrossRefGoogle Scholar
Ahlberg, P. 1989b. Agnostid trilobites from the Lower Ordovician Komstad Limestone Formation of Killeröd, Scania, Sweden. PALAEONTOLOGY 32, 553–70.Google Scholar
Ahlberg, P. 1989c. The type species of the Ordovician agnostid trilobite Geragnostus Howell, 1935. PALÄONTOL Z 63, 309–17.CrossRefGoogle Scholar
Ahlberg, P. 1990. Agnostid trilobites from the Ordovician of the Siljan district, Sweden. GEOL FÖREN STOCKH FÖRH 112, 145–56.CrossRefGoogle Scholar
Angelin, N. P. 1851. Palaeontologia Svecica. I: Iconographia crustaceorum formationis transitionis. Fasc. 1. Lund.Google Scholar
Angelin, N. P. [posthumous] 1878. Palaeontologia Scandinavica. T. Crustacea formationis transitionis. Fasc. 1 and 2. Holmiae (Stockholm). [Ed Lindström, G.].Google Scholar
Balashova, E. A. 1961. Nekotorye tremadokskie trilobity Aktyubinskoy Oblasti. [Some Tremadocian trilobites from the Aktyubinsk Oblast.] TRUDY GEOL INST AKAD NAUK SSSR 18, 102–45. [In Russian.]Google Scholar
Barrande, J. 1846. Notice préliminaire sur le Systême silurien et les Trilobites de Bohême. Leipsic.CrossRefGoogle Scholar
Berard, P. 1986. Trilobites de l'Ordovicien inferieur des Monts de Cabrieres (Montagne Noire - France). MEM CENT ETUD RECH GEOL HYDROL 24, 1220. Université des Sciences et Techniques du Languedoc (Montpellier II).Google Scholar
Bergström, J. 1982. Scania. In Bruton, D. L. & Williams, S. H. (eds.) Field excursion guide. IV International Symposium on the Ordovician System. PALEONTOL CONTR UNIV OSLO 279, 184–97.Google Scholar
Billings, E. 1861-1865. Palaeozoic fossils. Volume 1. Containing descriptions and figures of new or little known species of organic remains from the Silurian rocks. Montreal: Geological Survey of Canada.Google Scholar
Bohlin, B. 1949. The Asaphus Limestone in northernmost Öland. BULL GEOL INST UNIV UPSALA 33, 529–70.Google Scholar
Bruton, D. L., Lindström, M. & Owen, A. W. 1985. The Ordovician of Scandinavia. In Gee, D. G. & Sturt, B. A. (eds) The Caledonide Orogen—Scandinavia and related areas, 273–82. Chichester: John Wiley & Sons Ltd.Google Scholar
Bruun, Å. 1985. Paleozoisk berggrund. In Persson, L., Bruun, Å. & Vidal, G. Beskrivning till berggrundskartan Hjo SO. SVER GEOL UNDERS Af 134, 91111.Google Scholar
Capera, J. C., Courtessole, R. & Pillet, J. 1978. Contribution à l'étude de l'Ordovicien inférieur de la Montagne Noire, biostratigraphie et révision des Agnostida. ANN SOC GEOL NORD 98, 6788.Google Scholar
Cooper, R. A. & Lindholm, K. 1990. A precise worldwide correlation of early Ordovician graptolite sequences. GEOL MAG 127, 497525.CrossRefGoogle Scholar
Cooper, R. A., Fortey, R. A. & Lindholm, K. 1991. Latitudinal and depth zonation of early Ordovician graptolites. LETHAIA 24, 199218.CrossRefGoogle Scholar
Daily, B. & Jago, J. B. 1975. The trilobite Lejopyge Hawle and Corda and the middle-upper Cambrian boundary. PALAEONTOLOGY 18, 527–50.Google Scholar
Dean, W. T. 1966. The Lower Ordovician stratigraphy and trilobites of the Landeyran Valley and the neighbouring district of the Montagne Noire, south-western France. BULL BR MUS (NAT HIST) GEOL 12, 247353.Google Scholar
Dean, W. T. 1973. The Lower Palaeozoic stratigraphy and faunas of the Taurus Mountains near Beysehir, Turkey, III. The trilobites of the Sobova Formation (Lower Ordovician). BULL BR MUS (NAT HIST) GEOL 24, 281348.Google Scholar
Flodén, T. 1984. Der Strukturbau im Seegebiet von Schweden. Z ANGEW GEOL 30, 116.Google Scholar
Fortey, R. A. 1980. The Ordovician trilobites of Spitsbergen. III. Remaining trilobites of the Valhallfonna Formation. NORSK POLARINST SKRIFT 171, 1163.Google Scholar
Fortey, R. A. 1984. Global earlier Ordovician transgressions and regressions and their biological implications. In Bruton, D. L. (ed.) Aspects of the Ordovician system, 3750. Oslo: Universitetsforlaget.Google Scholar
Fortey, R. A. & Owens, R. M. 1987. The Arenig Series in South Wales. BULL BR MUS (NAT HIST) GEOL 41, 69307.Google Scholar
Funkquist, H. P. A. 1919. Asaphusregionens omfattning i sydöstra Skåne och på Bornholm. ACTA UNIV LUND N F 2, 16(1), 155.Google Scholar
Goodarzi, F., Stasiuk, L. D. & Lindholm, K. 1988. Graptolite reflectance and thermal maturity of Lower and Middle Ordovician shales from Scania, Sweden. GEOL FÖREN STOCKH FÖRH 110, 225–36.CrossRefGoogle Scholar
Harper, D. A. T., Graham, J. R., Owen, A. W. & Donovan, S. K. 1988. An Ordovician fauna from Lough Shee, Partry Mountains, Co. Mayo, Ireland. GEOL J 23, 293310.CrossRefGoogle Scholar
Harrington, H. J. 1938. Sobre las faunas del Ordoviciano inferior del norte Argentino. REV MUS LA PLATA N S SECC PALEONTOL 1, 109289.Google Scholar
Harrington, H. J. & Leanza, A. F. 1957. Ordovician trilobites of Argentina. DEP GEOL UNIV KANSAS SPEC PUBL 1, 1276.Google Scholar
Hawle, I. & Corda, A. J. C. 1847. Prodrom einer Monographie der böhmischen Trilobiten. Prague: J. G. Calve.Google Scholar
Holm, G. 1882a. Om de viktigaste resultaten från en sommaren 1882 utförd geologisk-palaeontologisk resa på Öland. ÖFVERS K SVEN VETENSKAPSAKAD FÖRH 1882(7), 6373.Google Scholar
Holm, G. 1882b. Ueber einige Trilobiten aus dem Phyllograptusschiefer Dalekarliens. BIH K SVEN VETENSKAPSAKAD HANDL 6(9), 116.Google Scholar
Holmer, L. E. & Popov, L. E. 1990. The acrotretacean brachiopod Ceratreta tanneri (Metzger) from the Upper Cambrian of Baltoscandia. GEOL FÖREN STOCKH FORH 112, 249–63.CrossRefGoogle Scholar
Holub, K. 1908. Přispěvek ku poznáni fauny pásma Ddly. [Contributions to the knowledge of the fauna in layer Ddly.] CESKÉ AKAD ROZPR II TRIDA 17(10), 119. [In Czech.]Google Scholar
Holub, K. 1912a. Doplňky ku fauně Eulomového horizontu v okoli Rokycan. [Additional remarks on the fauna from the Euloma horizon in the Rokycany area.] CESKE AKAD ROZPR II TRIDA 21(33), 112. [In Czech.]Google Scholar
Holub, K. 1912b. Nachträge zur Fauna des Euloma-Horizontes in der Umgebung von Rokycan. BULL INT ACAD SCI BOHEME 17, 14.Google Scholar
Howell, B. F. 1935. Cambrian and Ordovician trilobites from Hérault, southern France. J PALEONTOL 9, 222–38.Google Scholar
Jaanusson, V. 1957. Unterordovizische Illaeniden aus Skandinavien. BULL GEOL INST UNIV UPPSALA 37, 79165.Google Scholar
Jaanusson, V. 1973. Aspects of carbonate sedimentation in the Ordovician of Baltoscandia. LETHAIA 6, 1134.CrossRefGoogle Scholar
Jaanusson, V. 1976. Faunal dynamics in the Middle Ordovician (Viruan) of Balto-Scandia. In Bassett, M. G. (ed.) The Ordovician system: proceedings of a Palaeontological Association symposium, Birmingham, September 1974, 301326. Cardiff: University of Wales Press and National Museum of Wales.Google Scholar
Jaanusson, V. 1979. Ordovician. In Robison, R. A. & Teichert, C. (eds.) Treatise on Invertebrate Paleontology, Part A, Introduction, A136–A166. Lawrence: Geological Society of America & University of Kansas Press.Google Scholar
Jaanusson, V. 1982. Introduction to the Ordovician of Sweden. In Bruton, D. L. & Williams, S. H. (eds.) Field excursion guide. IV International Symposium on the Ordovician System. PALEONTOL CONTR UNIV OSLO 279, 19.Google Scholar
Jaanusson, V. & Bergström, S. M. 1980. Middle Ordovician faunal spatial differentiation in Baltoscandia and the Appalachians. ALCHERINGA 4, 89110.CrossRefGoogle Scholar
Jaekel, O. 1909. Über die Agnostiden. Z DEUTSCH GEOL GESELL 61, 380401.Google Scholar
Jago, J. B. 1976. Late Middle Cambrian agnostid trilobites from north-western Tasmania. PALAEONTOLOGY 19, 133–72.Google Scholar
Kobayashi, T. 1939. On the agnostids (Part I). J FAC SCI UNIV TOKYO, SEC II 5, 69198.Google Scholar
Kobayashi, T. & Hamada, T. 1978. Upper Ordovician trilobites from the Langkawi Islands, Malaysia. GEOL PALAEONTOL SE ASIA 19, 127.Google Scholar
Koroleva, M. N. 1982. Trilobity ordovika severo-vostochnogo Kazakhstana. [Ordovician trilobites of north-east Kazakhstan.] Moscow: Nedra. [In Russian.]Google Scholar
Lespérance, P. J. & Sheehan, P. M. 1988. Trilobites et Brachiopodes ashgilliens (Ordovicien supérieur) de l' “Assise” de Fosse, Bande de Sambre-Meuse (Belgique). BULL INST R SCI NAT BELG SCI TERRE 57, 91123.Google Scholar
Lindholm, K. 1991. Hunnebergian graptolites and biostratigraphy in southern Scandinavia. LUND PUBL GEOL 95, 136.Google Scholar
Lindström, G. 1888. List of the fossil faunas of Sweden 1. Cambrian and Lower Silurian. Stockholm.Google Scholar
Lindström, M. 1971. Vom Anfang, Hochstand und Ende eines Epikontinentalmeeres. GEOL RUNDSCHAU 60, 419438.CrossRefGoogle Scholar
Lindström, M. 1979. Diagenesis of Lower Ordovician hardgrounds in Sweden. GEOL PALAEONTOL 13, 930.Google Scholar
Lindström, M. & Vortisch, W. 1983. Indications of upwelling in the Lower Ordovician of Scandinavia. In Thiede, J. & Suess, E. (eds) Coastal Upwelling, Pt. B, 535–51. New York and London: Plenum Publishing Co.Google Scholar
Linnarsson, J. G. O. 1866. Om de Siluriska Bildningarne i Mellersta Westergötland. I. Stockholm.Google Scholar
Linnarsson, J. G. O. 1869. Om Vestergötlands cambriska och siluriska aflagringar. K SVEN VETENSKAPSAKAD HANDL 8(2), 189.Google Scholar
Linnarsson, G. & Tullberg, S. A. 1882. Beskrifning till kartbladet Vreta Kloster. SVER GEOL UNDERS Aa 83, 145.Google Scholar
Löfgren, A. 1978. Arenigian and Llanvirnian conodonts from Jämtland, northern Sweden. FOSSILS STRATA 13, 1129.CrossRefGoogle Scholar
Löfgren, A. 1985. Early Ordovician conodont biozonation at Finngrundet, south Bothnian Bay, Sweden. BULL GEOL INST UNIV UPPSALA N S 10, 115128.Google Scholar
Ludvigsen, R., Westrop, S. R. & Kindle, C. H. 1989. Sunwaptan (Upper Cambrian) trilobites of the Cow Head Group, western Newfoundland. PALAEONTOGR CANADIANA 6, 1175.Google Scholar
Männil, R. 1966. Istoriya razvitiya Baltiyskogo basseyna v ordovike. [Evolution of the Baltic Basin during the Ordovician.] Tallinn: Eesti NSV Teaduste Akad. Geol. Inst. [In Russian with English summary.]Google Scholar
Moberg, J. C. 1890. Anteckningar om Ölands ortocerkalk. SVER GEOL UNDERS C109, 1122.Google Scholar
Moberg, J. C. 1910. The Silurian area of Fogelsång. GEOL FÖREN STOCKH FÖRH 32, 6384.Google Scholar
Moberg, J. C. & Segerberg, C. O. 1906. Bidrag till kännedomen om Ceratopygeregionen med särskild hänsyn till dess utveckling i Fogelsångstrakten. ACTA UNIV LUND N F 2, 2(7), 1113.Google Scholar
Moore, R. C. (ed.) 1959. Treatise on Invertebrate Paleontology, Part O, Arthropoda 1. Lawrence: Geological Society of America & University of Kansas Press.Google Scholar
Nordlund, U. 1988. Lower Ordovician carbonate sedimentology and lithostratigraphy of northern Öland, Sweden. ACTA UNIV UPS COMPR SUMM UPPSALA DISS FAC SCI 170, 110.Google Scholar
Nordlund, U. 1989. Lateral facies changes in the Lower Ordovician of northern Öland, Sweden. GEOL FÖREN STOCKH FÖRH 111, 261–72.CrossRefGoogle Scholar
Novák, O. 1883. Zur Kenntniss der böhmischen Trilobiten. BEITR PALÄONTOL GEOL ÖSTERR-UNG 3, 2363.Google Scholar
Olin, E. 1906. Om de chasmopskalken och trinucleusskiffern motsvarande bildningarne i Skåne. ACTA UNIV LUND N F 2, 2(3), 179.Google Scholar
Öpik, A. A. 1961. The geology and palaeontology of the headwaters of the Burke River, Queensland. BULL BUR MINER RESOUR GEOL GEOPHYS AUST 53, 1249.Google Scholar
Öpik, A. A. 1967 The Mindyallan fauna of north-western Queensland. BULL BUR MINER RESOUR GEOL GEOPHYS AUST 74, 1404.Google Scholar
Öpik, A. A. 1979. Middle Cambrian agnostids: systematics and biostratigraphy. BULL BUR MINER RESOUR GEOL GEOPHYS AUST 172, 1188.Google Scholar
Owen, A. W. 1981. The Ashgill trilobites of the Oslo Region, Norway. PALAEONTOGR ABT A175, 188.Google Scholar
Palmer, A. R. 1955. Upper Cambrian Agnostidae of the Eureka district, Nevada. J PALEONTOL 29, 86101.Google Scholar
Pek, I. 1977. Agnostid trilobites of the Central Bohemian Ordovician. SB GEOL VED PALEONTOL 19, 744.Google Scholar
Pek, I. & Prokop, R. J. 1984. New finds of the agnostid trilobites from the Ordovician of the Prague area (Czechoslovakia). CASOPIS NAROD MUZEA 153, 1720.Google Scholar
Shanchi, Peng 1990a. Tremadoc stratigraphy and trilobite faunas of northwestern Hunan. 1. Trilobites from the Nantsinkwan Formation of the Yangtze Platform. BERINGERIA 2, 353.Google Scholar
Shanchi, Peng 1990b. Tremadoc stratigraphy and trilobite faunas of northwestern Hunan. 2. Trilobites from the Panjiazui Formation and the Madaoyu Formation in Jiangnan Slope Belt. BERINGERIA 2, 55171.Google Scholar
Perner, J. (ed.) 1918. Trilobiti pásma D-dly z okoli Pražského (Die Trilobiten der Zone D-dly von Prag und Umgebung). PALAEONTOGR BOHEMIAE 9, 155.Google Scholar
Rabano, I. 1989. Trilobites del Ordovicico Medio del sector meridional de la zona Centroibérica española. Parte II: Agnostina y Asaphina. BOL GEOL MIN 100, 541609.Google Scholar
Rábano, I., Pek, I. & Vaněk, J. 1985. New Agnostina (Trilobita) from the Llanvirn (Ordovician) of Spain. ESTUD GEOL 41, 439–45.CrossRefGoogle Scholar
Raymond, P. E. 1913. Some changes in the names of genera of trilobites. OTTAWA NAT 26, 137–42.Google Scholar
Raymond, P. E. 1925. Some trilobites of the lower Middle Ordovician of eastern North America. BULL MUS COMP ZOOL HARVARD 67, 1180.Google Scholar
Regnéll, G. 1942. Stratigraphical and paleontological remarks on the Lower Ordovician of central and northern Öland with special reference to Köpings klint. MEDD LUNDS GEOLMINERAL INST 99, 117.Google Scholar
Robison, R. A. 1964. Late Middle Cambrian faunas from western Utah. J PALEONTOL 38, 510–66.Google Scholar
Robison, R. A. 1982. Some Middle Cambrian agnostoid trilobites from western North America. J PALEONTOL 56, 132–60.Google Scholar
Robison, R. A. & Pantoja-Alor, J. 1968. Tremadocian trilobites from the Nochixtlán region, Oaxaca, Mexico. J PALEONTOL 42, 767800.Google Scholar
Robison, R. A., Rosova, A. V., Rowell, A. J. & Fletcher, T. P. 1977. Cambrian boundaries and divisions. LETHAIA 10, 257–62.CrossRefGoogle Scholar
Rosén, S. 1916. Zur Frage des Vorhandenseins von dem Oboluskonglomerate entsprechenden Bildungen in Östergötland. BULL GEOL INST UNIV UPPSALA 15, 213–18.Google Scholar
Ross, R. J. 1958. Trilobites in a pillow-lava of the Ordovician Valmy Formation, Nevada. J PALEONTOL 32, 559–70.Google Scholar
Ross, R. J. 1967. Some Middle Ordovician brachiopods and trilobites from the Basin Ranges, western United States. PROF PAP US GEOL SURV 523–D, D143.Google Scholar
Rowell, A. J., Robison, R. A. & Strickland, D. K. 1982. Aspects of Cambrian agnostoid phylogeny and chronocorrelation. J PALEONTOL 56, 161–82.Google Scholar
Salter, J. W. 1864. A monograph of the British trilobites from the Cambrian, Silurian, and Devonian formations. PALAEONTOGR SOC MONOGR, 180.Google Scholar
Schmidt, F. 1894. Revision der ostbaltischen silurischen Trilobiten. Abt. 4. Calymmeniden, Proetiden, Bronteiden, Harpediden, Trinucleiden, Remopleuriden und Agnostiden. MEM ACAD IMP SCI ST PETERSBURG (7) 42(5), 193.Google Scholar
Sdzuy, K. 1955. Die Fauna der Leimitz-Schiefer (Tremadoc). ABH SENCKENBERG NATURFORSCH GES 492, 174.Google Scholar
Sdzuy, K. 1958. Fossilien aus dem Tremadoc der Montagne Noire. SENCKENBERGIANA LETHAEA 39, 255–85.Google Scholar
Shergold, J. H. 1972. Late Upper Cambrian trilobites from the Gola Beds, western Queensland. BULL BUR MINER RESOUR GEOL GEOPHYS AUST 112, 1127.Google Scholar
Shergold, J. H. 1975. Late Cambrian and Early Ordovician trilobites from the Burke River Structural Belt, western Queensland, Australia. BULL BUR MINER RESOUR GEOL GEOPHYS AUST 153, 1251.Google Scholar
Shergold, J. H., Laurie, J. R. & Sun, 1990. Classification and review of the trilobite order Agnostida Salter, 1864: an Australian perspective. BUR MINER RESOUR GEOL GEOPHYS AUST REP 296, 193.Google Scholar
Shergold, J. H. & Sdzuy, K. 1984. Cambrian and early Tremadocian trilobites from Sultan Dag, central Turkey. SENCKENBERGIANA LETHAEA 65, 51135.Google Scholar
Stouge, S. & Bagnoli, G. 1990. Lower Ordovician (Volkhovian-Kundan) conodonts from Hagudden, northern Öland, Sweden. PALAEONTOGR ITAL 77, 154.Google Scholar
Thorslund, P. 1940. On the Chasmops Series of Jemtland and Södermanland (Tvären). SVER GEOL UNDERS C436, 1191.Google Scholar
Tjernvik, T. E. 1952. Om de lägsta ordoviciska lagren i Närke. GEOL FÖREN STOCKH FÖRH 74, 5170.CrossRefGoogle Scholar
Tjernvik, T. E. 1956. On the Early Ordovician of Sweden-stratigraphy and fauna. BULL GEOL INST UNIV UPPSALA 36, 107284.Google Scholar
Tjernvik, T. E. 1960. The Lower Didymograptus Shales of the Flagabro drilling core. GEOL FÖREN STOCKH FÖRH 82, 203–17.CrossRefGoogle Scholar
Tjernvik, T. E. & Johansson, J. V. 1980. Description of the upper portion of the drill-core from Finngrundet in the South Bothnian Bay. BULL GEOL INST UNIV UPPSALA N S 8, 173204.Google Scholar
Törnquist, S. L. 1874. Om Siljanstraktens paleozoiska formationsled. ÖFVERS K SVEN VETENSKAPSAKAD FÖRH 1874(4), 339.Google Scholar
Törnquist, S. L. 1875. Berättelse om en geologisk resa genom Skånes och Östergötlands paleozoiska trakter, sommaren 1875. ÖFVERS K SVEN VETENSKAPSAKAD FÖRH 1875 (10), 4370.Google Scholar
Törnquist, S. L. 1884. Undersökningar öfver Siljansområdets trilobitfauna. SVER GEOL UNDERS C66, 1101.Google Scholar
Tripp, R. P., Zhiyi, Zhou; &Zhenqin, Pan 1989. Trilobites from the Upper Ordovician Tangtou Formation, Jiangsu Province, China. TRANS R SOC EDINBURGH EARTH SCI 80, 2568.CrossRefGoogle Scholar
Troedsson, G. T. 1937. On the Cambro-Ordovician faunas of western Quruq tagh, eastern T'ien-shan. PALAEONTOL SIN, NEW SER B 2 (whole series no. 106), 174.Google Scholar
Tullberg, S. A. 1882. Förelöpande redogörelse för geologiska resor på Öland. GEOL FÖREN STOCKH FÖRH 6, 220–36.CrossRefGoogle Scholar
Westergård, A. H. 1931. Den kambro-siluriska lagerserien. In Lundqvist, G., Högbom, A. & Westergård, A. H. Beskrivning till kartbladet Lugnås. SVER GEOL UNDERS Aa 172, 2967.Google Scholar
Westergård, A. H. 1943. Den kambro-siluriska lagerserien. In Johansson, S., Sundius, N. & Westergård, A. H. Beskrivning till kartbladet Lidköping. SVER GEOL UNDERS Aa 182, 2289.Google Scholar
Westergård, A. H. 1946. Agnostidea of the Middle Cambrian of Sweden. SVER GEOL UNDERS C477, 1140.Google Scholar
Whitehouse, F. W. 1936. The Cambrian faunas of north-eastern Australia. Parts 1 and 2. MEM QUEENSLAND MUS 11, 59112.Google Scholar
Whittard, W. F. 1955. The Ordovicain trilobites of the Shelve Inlier, west Shropshire. 1. PALAEONTOGR SOC MONOGR, 140.Google Scholar
Whittington, H. B. 1963. Middle Ordovician trilobites from Lower Head, western Newfoundland. BULL MUS COMP ZOOL HARVARD 129, 1118.Google Scholar
Whittington, H. B. 1965. Trilobites of the Ordovician Table Head Formation, western Newfoundland. BULL MUS COMP ZOOL HARVARD 132, 275441.Google Scholar
Wiman, C. 1893. Ueber die Silurformationen in Jemtland. BULL GEOL INST UNIV UPPSALA 1, 256–76.Google Scholar
Wiman, C. 1905. Ein Shumardiaschiefer bei Lanna in Nerike. ARK ZOOL 2(11), 120.Google Scholar
Tian-rong, Zhou 1981. New materials of early Tremadocian trilobites from Sandu and Pu'an, Guizhou. ACTA PALAEONTOL SIN 20, 241–6. [In Chinese with English summary.]Google Scholar
Zhi-yi, Zhou 1987. Notes on Chinese Ordovician agnostids. ACTA PALAEONTOL SIN 26, 639–61. [In Chinese with English summary.]Google Scholar
Zhiyi, Zhou & Dean, W. T. 1986. Ordovician trilobites from Chedao, Gansu Province, north-west China. PALAEONTOLOGY 29, 743–86.Google Scholar