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VI.—Features of Placoderm Diversification and the Evolution of the Arthrodire Feeding Mechanism*.

Published online by Cambridge University Press:  06 July 2012

Roger S. Miles
Affiliation:
Department of Geology, Royal Scottish Museum, Edinburgh.

Synopsis

The initial adaptive radiation of the Placodermi took place rapidly following the development of the basic placoderm adaptive complex after the ancestral scale covering of the trunk fused into a rigid shield, and not long before the group appears in the fossil record in the Lower Devonian. The radiation was mainly concerned with different ways of living in the benthos of a variety of marine and fresh-water environments; a few nektonic species appear late in the history of the Arthrodira. The fossil record shows the evolution of the orders in their adaptive zones. The zones become increasingly distinct as the orders evolve and become more specific in their adaptations, and the arthrodire, antiarch and rhenanid zones segregate into successively occupied sub-zones. The evolution of the Placodermi has been previously described in terms of improvements in the locomotor mechanism by an analysis of changes in the trunk-armour and pectoral fins. A more detailed description can be given by considering the feeding mechanism as well; this is particularly true of the largest order, the Arthrodira. Study of the feeding mechanism involves the cervical joints as well as the jaws and gnathals. The cervical joints had the same functions in feeding as the anterior part of the vertebral column (“the neck”) in many higher fish. In arthrodires jaw action involved vertical movements of the mandibular lever; the upper jaw apparatus is comparable to the rigid palatoquadrate-maxillary complex of primitive bony fish. The mandible was transformed into a bent lever in Brachyosteus by the development of a small “coronoid” process, but the arthrodire jaw apparatus remained undeveloped in comparison with Actinopterygii and Elasmobranchii. Arthrodire jaw suspension was autostylic. Evidence from the Rhenanida and Ptyctodontida has been interpreted to suggest that this condition was secondary, and that primitive placoderms had an elasmobranch or holocephalan-like palatoquadrate with hyostylic suspension. This view is not entirely supported by the state of the palatoquadrate in primitive arthrodires, but there is no good evidence that placoderms had a complete, open spiracular gill-slit (the aphethoyoid condition). Arthrodire phylogeny cannot yet be described in vertical lines, but four successive levels of organization of increasing efficiency can be recognized; the actinolepid, phlyctaenaspid, coccosteomorph and pachyosteomorph levels. These levels can be defined by simple characters relating to broad adaptations in the locomotor and feeding mechanisms. Evolutionary trends in the Arthrodira include the enlargement of the scapulocoracoid and base of the pectoral fin and the reduction of the spinal plate and flank armour, as the fish gain better control in the water and more myomeres become available for use in swimming; and the enlargement of the nuchal gap and development of the cranio-thoracic joint as powerful muscles are developed to raise the head to give a wide gape, accompanied by the specialization of the gnathals for different modes of feeding. Some of these trends are reversed in compressed, nektonic species. The description of arthrodire phylogeny in terms of changes that can be understood from a functional point of view reveals interesting examples of mosaic and parallel evolution. Parabelosteus n.gen. is erected.

Type
Research Article
Copyright
Copyright © Royal Society of Edinburgh 1969

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References

References to Literature

Abel, O., 1927. “Ein Beitrag zur Kenntnis von Heterostius convexus Asmuss aus den Alten Roten Sandstein von Arokülla bei Dorpat; die Gelenkverbindung zwishen den Schädeldach und dem Rumpfpanzer”, Paläont. Z., 9, 314319.CrossRefGoogle Scholar
Adams, L. A., 1919. “A memoir on the phylogeny of the jaw musculature in Recent and fossil vertebrates”, Ann. N. Y. Acad. Sci, 28, 51166.CrossRefGoogle Scholar
Alexander, R. McN., 1967. Functional design in fishes., Hutchinson, London.Google Scholar
Breder, C. M. Jr., 1925. “On the feeding behaviour of fishes with terminal mouths”, Copeia, 1925, 8991.CrossRefGoogle Scholar
Chang, M.-M., 1966. “Notes on some vertebrates from the Lower Devonian of Yunnan, China”, Preprint: Colloques Int. Cent. Natn. Rech. Scient., 163, (Paris, June 1966).Google Scholar
Dean, B., 1901. “On two new arthrodires from the Cleveland shale of Ohio”, Mem. N. Y. Acad. Sci., 2, 87100.Google Scholar
Dean, B., 1906. “Chimaeroid fishes and their development”, Publs Carnegie Instn, 32, 1194.Google Scholar
Dean, B., 1909. “Studies on fossil fishes (sharks, chimaeroids, and arthrodires)”, Mem. Am. Mus. Nat. Hist., 9, 211287.Google Scholar
De Beer, G. R., 1937. The development of the vertebrate skull., Oxford.Google Scholar
De Beer, G. R., 1954. “Archaeopteryx, and evolution”, Adv. Sci., 42, 111.Google Scholar
Denison, R. H., 1950. “A new arthrodire from the New York State Devonian”, Am. J. Sci., 248, 565580.CrossRefGoogle Scholar
Denison, R. H., 1956. “A review of the habitat of the earliest vertebrates”, Fieldiana, Geol, 11, 359457.Google Scholar
Denison, R. H., 1958. “Early Devonian fishes from Utah. 3. Arthrodira”, Fieldiana, Geol., 11, 459551.Google Scholar
Denison, R. H., 1960. “Fishes of the Devonian Holland Quarry Shale of Ohio”, Fieldiana, Geol, 11, 555613.Google Scholar
Denison, R. H., 1961. “Feeding mechanisms of Agnatha and early gnathostomes”, Am. Zoologist, 1, 177181.CrossRefGoogle Scholar
Denison, R. H., 1962. “A reconstruction of the shield of the arthrodire Bryantolepis brachycephalus, (Bryant)”, Fieldiana, Geol, 14, 99104.Google Scholar
Dunkle, D. H., 1947. “A new genus and species of arthrodiran fish from the Upper Devonian Cleveland Shale”, Scient. Publs Cleveland Mus. Nat. Hist., 8, 103117.Google Scholar
Dunkle, D. H. & Bungart, P. A., 1939. “A new arthrodire from the Cleveland Shale formation”, Scient., Publs Cleveland Mus. Nat. Hist., 8, 1327.Google Scholar
Dunkle, D. H., 1940. “On one of the least known of the Cleveland Shale Arthrodira”, Scient. Publs Cleveland Mus., Nat. Hist., 8, 2947.Google Scholar
Dunkle, D. H., 1942 a. “The infero-gnathal plates of Titanichthys”, Scient. Publs Cleveland Mus. Nat. Hist., 8, 4959.Google Scholar
Dunkle, D. H., 1942 b. “A new genus and species of Arthrodira from the Cleveland Shale”, Scient. Publs Cleveland, Mus. Nat. Hist., 8, 6571.Google Scholar
Dunkle, D. H., 1943. “Comments on Diplognathus mirabilis, Newberry”, Scient. Publs Cleveland Mus. Nat. Hist., 8, 7384.Google Scholar
Dunkle, D. H., 1945. “A new arthrodiran fish from the Upper Devonian Ohio Shales”, Scient. Publs Cleveland Mus., Nat. Hist., 8, 8595.Google Scholar
Dunkle, D. H., 1946. “The antero-supragnathal of Gorgonichthys”, Amer. Mus. Nov., 1316, 110.Google Scholar
Eastman, C. R., 1897. “On the relations of certain plates in the dinichthyids”, Bull. Mus. Comp. Zool Harv., 31, 1943.Google Scholar
Eastman, C. R., 1898. “Some new points in dinichthyid osteology”, Proc. Am. Ass. Advmt Sci., 47, 371372.Google Scholar
Eastman, C. R., 1906. “Dipnoan affinities of arthrodires”, Am. J. Sci., 21, 131143.CrossRefGoogle Scholar
Eastman, C. R., 1908. “Devonic fishes of the New York formations”, Mem. N. Y. St. Mus., 10, 1235.Google Scholar
Eaton, T. E. Jr., 1939. “Suggestions on the evolution of the operculum of fishes”, Copeia, 1939, 4246.CrossRefGoogle Scholar
Edgeworth, F. H., 1935. The cranial muscles of vertebrates. Cambridge Univ. Press.Google Scholar
Gans, C. & Bock, W., 1965. “The functional significance of muscle architectur—a theoretical analysis”, Ergebn. Anat. EntwGesch., 38, 115142.Google ScholarPubMed
Geuenich, E., 1939. “Paläobiologische Studien an Arthrodiren”, Palaeobiologica, 7, 1029.Google Scholar
Gross, W., 1931. “Asterolepis ornata, Eichw. und das Antiarch-Problem”, Palaeontographica, 75, 162.Google Scholar
Gross, W., 1932. “Die Arthrodira Wildungens”, Geol. Palaont. Abh., 19, 161.Google Scholar
Gross, W., 1933. “Die Wirbeltiere des rheinischen Devons”, Abh. Preuss. Geol. Landesanst., 154, 183.Google Scholar
Gross, W., 1937. “Die Wirbeltiere des rheinischen Devons II”, Abh. Preuss. Geol. Landesanst., 176, 583.Google Scholar
Gross, W., 1938. “Rhachiosteus pterygiatus, n. gen. n. sp. (Euarthrodira, Brachythoraci)”, Decheniana, 97A, 183208.Google Scholar
Gross, W., 1941. “Die Bothriolepis-arten, der Cellulosa-Mergel, Lettlands”, K. Svenska VetenskAkad. Handl., 19, 179.Google Scholar
Gross, W., 1950. “Die paläontologische und stratigraphische Bedeutung der Wirbeltierfaunen des Old Reds und der marinen altpaläozoischen Schichten”, Abh. Dt. Akad. Wiss. Berl, Math.-Nat. Kl, 1949, 130.Google Scholar
Gross, W., 1957. “Mundzähne und Hautzahne der Acanthodier und Arthrodiren”, Palaeontographica, 109A, 140.Google Scholar
Gross, W., 1958. “Über die älteste Arthrodiren-Gattung”, Notizbl. Hess. Landesamt. Bodenforsch. Wiesbaden, 86, 730.Google Scholar
Gross, W., 1959. “Arthrodiren aus dem Obersilur der Prager Mulde”, Palaeontographica, 113A, 135.Google Scholar
Gross, W., 1960. “Tityosteus, n. gen., ein Riesenarthrodire aus dem rheinischen Unterdevon”, Paläont., Z., 34, 263274.CrossRefGoogle Scholar
Gross, W., 1961. “Lunaspis broilii, und Lunaspis heroldi, aus dem Hunsrückschiefer (Unterdevon, Rheinland)”, Notizbl. Hess. Landesamt. Bodenforsch. Wiesbaden, 89, 1743.Google Scholar
Gross, W., 1962 a. “Peut-on homologuer les os des arthrodires et des téléostomes?”, Colloques Int. Cent. Natn., Rech. Scient., 104, 6974.Google Scholar
Gross, W., 1962 b. “Neuuntersuchung der Stensiöellida (Arthrodira, Unterdevon)”, Notizbl. Hess. Landesamt., Bodenforsch. Wiesbaden, 90, 4886.Google Scholar
Gross, W., 1962 c. “Neuuntersuchung der Dolichothoraci aus dem Unterdevon von Overath bei Köln”, Paläont. Z., H. Schmidt-Festband, 4563.CrossRefGoogle Scholar
Gross, W., 1963. “Gemuendina stuertzi, Traquair. Neuuntersuchung”, Notizbl. Hess. Landesamt. Bodenforsch., Wiesbaden, 91, 3673.Google Scholar
Gross, W., 1965. “Über die Placodermen-Gattung Asterolepis,und Tiaraspis, aus dem Devon Belgiens und einen fraglichen Tiaraspis-Rest, aus dem Devon Spitzbergens”, Bull. Inst. Roy. Sci. Nat. Belg., 41, 119.Google Scholar
Gross, W., 1967. “Über das Gebiss der Acanthodier und Placodermen”, J. Linn. Soc. (Zool), 47, 121130.CrossRefGoogle Scholar
Hecht, M. K., 1965. “The role of natural selection and evolutionary rates in the origin of higher levels of organization”, Syst. Zool, 14, 301317CrossRefGoogle ScholarPubMed
Heintz, A., 1929. “Die downtonischen und devonischen Vertebraten von Spitzbergen. II. Acanthaspida”, Skr. Svalbard Ishavet, 22, 181.Google Scholar
Heintz, A., 1930. “Eine neue Rekonstruktion von Heterostius, ASM.”, Protok. Obshch. Estest., Yur'ev, 36, 17.Google Scholar
Heintz, A., 1931. “A reconstruction of Stenognathus gouldi, (Newberry)”, Ann. Mag. Nat. Hist., 8, 242249.CrossRefGoogle Scholar
Heintz, A., 1932 a. “The structure of Dinichthys. A contribution to our knowledge of the Arthrodira”, Am. Mus., Nat. Hist., BashfordDean Mem. Vol., 4, 115224.Google Scholar
Heintz, A., 1932 b. “Beitrag zur Kenntnis der devonischen Fischfauna Ost-Grönlands”, Skr. Svalbard Ishavet, 42, 127.Google Scholar
Heintz, A., 1932 c. “Über einige Fischreste aus dem Hunsrück-Schiefer”, Z. Miner. Geol. Paläont, 1932B, 572582.Google Scholar
Heintz, A., 1933. “Some remarks about the structure of Phlyctaenaspis acadica, Whiteaves”, Norsk Geol. Tidsskr., 14, 127144.Google Scholar
Heintz, A., 1934. “Revision of the Estonian Arthrodira. Pt. 1. Family Homostiidae, Jaekel”, Arch. Naturk., Eestis, 10, 177290.Google Scholar
Heintz, A., 1938. “Notes on Arthrodira”, Norsk Geol. Tidsskr., 18, 127.Google Scholar
Heintz, A., 1962. “New investigation on the structure of Arctolepis, from the Devonian of Spitsbergen”, Årbok, Norsk Polarinst, 1961, 2340.Google Scholar
Hills, E. S., 1958. “A brief review of Australian fossil vertebrates”. In Westoll, T. S.: Studies on fossil vertebrates, Univ. London: Athlone Press.Google Scholar
Holmgren, N., 1943. “Studies on the head of fishes. An embryological, morphological, and phylogenetical study. 4. General morphology of the head in fish”, Acta. Zool. Stockh., 24, 1188.CrossRefGoogle Scholar
Hoover, K. V., 1960. “Devonian-Mississippian shale sequence in Ohio”, Inf. Circ. Div. Geol. Surv. Ohio, 27, 1154.Google Scholar
Hussakof, L., 1906. “Studies on the Arthrodira”, Mem. Am. Mus. Nat. Hist., 9, 105154.Google Scholar
Hussakof, L., 1909. “The systematic relationships of certain American arthrodires”, Bull. Am. Mus. Nat. Hist., 26, 263272.Google Scholar
Hussakof, L. & Bryant, W. L., 1918. “Catalog of the fossil fishes in the museum of the Buffalo society of natural sciences”, Bull. Buffalo Soc. Nat. Sci., 12, 1198.Google Scholar
Huxley, J. S., 1958. “Evolutionary processes and taxonomy with special reference to grades”, Uppsala Univ., Årsskr., 1958, 2138.Google Scholar
Jaekel, O., 1906. “Einige Beiträge zur Morphologie der ältesten Wirbeltiere”, Sber. Ges. Naturf. Freunde Berl, 1906, 180189.Google Scholar
Jaekel, O., 1919. “Die Mundbildung der Placodermen”, Sber. Ges. Naturf. Freunde Berl, 1919, 73110.Google Scholar
Jaekel, O., 1927. “Untersuchungen über die Fischfauna von Wildungen”, Paläont. Z., 9, 329339.CrossRefGoogle Scholar
Jarvik, E., 1960. Théories de l'évolution des Vertébrés reconsidérées à la lumière des récentes découverts sur les, Vertébrés inférieurs., Masson et Cie, Paris.Google Scholar
Jarvik, E., 1963. “The composition of the intermandibular division of the head in fish and tetrapods and the diphyletic origin of the tetrapod tongue”, K. Svenska VetenskAkad. Handl, 9, 174.Google Scholar
Jarvik, E., 1964. “Specializations in early vertebrates”, Annls Soc. Roy. Zool. Belg., 94, 1195.Google Scholar
Karatajūtė-Talimaa, V., 1960. Byssacanthus dilatatus, (Eichw.) from the Middle Devonian of the U.S.S.R. Colnea Acta Geol. Lithuanica, 1960, 293305.Google Scholar
Karatajūtė-Talimaa, V., 1963. Genus Asterolepis, from the Devonian of the Russian Platform. In Grigelis, A. & KaratajūtĖ-Talimaa, V.: The date of the geology of the Lithuania. Vilnius. (In Russian with English and Lithuanian summaries).Google Scholar
Kulczycki, J., 1957. “Upper Devonian fishes from the Holy Cross Mountains (Poland)”, Acta Palaeont., Pol, 2, 285380.Google Scholar
Lehman, J. P., 1956. “Les arthrodires du Dévonian Superieur du Tafilalet (Sud marocain)”, Notes Mém. Serv., Mines Carte Géol Maroc, 129, 170.Google Scholar
Lehman, J. P., 1962. “A propos de la double articulation de la cuirasse des arthrodires”, Collogues Int. Cent. Natn., Rech. Scient., 104, 6367.Google Scholar
Liu, H. T., 1955. “Kiangyousteus, a new arthrodiran fish from Szechuan, China”, Acta Palaeont. Sin., 3, 261274.Google Scholar
Liu, Y.-H., 1963. “On the Antiarchi from Chutsing”, Vertebr. Palasiat., 7, 8085.Google Scholar
Luther, A., 1909. “Untersuchungen über die von N. trigeminus innervierte Musculatur der Selachier (Haie und Rochen) unter Berücksichtigung ihrer Beziehungen zu benachbarten Organen”, Acta Soc. Sci. Fenn., 36, 1176.Google Scholar
Mark, E. J., 1953. “Genus Holonema, from the Middle Devonian of Estonian S.S.R.”, Loodusuurijate Seltsi, Juubelikoguteos, 18531953, Tallinn, 1953, 382396. (In Russian).Google Scholar
Mark, E. J., 1963. “On the spinal plate of the Middle Devonian arthrodire Homostius”, Geoloogia-Inst. Uurim., 13, 189199. (In Russian with English and Estonian summaries).Google Scholar
Matthes, H., 1963. “A comparative study of the feeding mechanism of some African Cyprinidae (Pisces, Cypriniformes)”, Bijdr. Dierk., 33, 335.CrossRefGoogle Scholar
Miles, R. S., 1962. “Gemuendenaspis, n. gen., an arthrodiran fish from the Lower Devonian Hunsrückschiefer of Germany”, Trans Roy. Soc. Edinb., 65, 5977.CrossRefGoogle Scholar
Miles, R. S., 1964 a. “A reinterpretation of the visceral skeleton of Acanthodes”, Nature, Lond., 204, 457459.CrossRefGoogle Scholar
Miles, R. S., 1964 b. “On some coccosteomorph arthrodires from the Devonian of Arizona”, Ark. Zool, 16, 427460.Google Scholar
Miles, R. S., 1965. “Description of fish plate”, Antardic Res. Ser., 6, 213214.Google Scholar
Miles, R. S., 1966 a. “The placoderm fish Rhachiosteus pterygiatus, Gross and its relationships”, Trans. Roy. Soc., Edinb., 66, 377392.Google Scholar
Miles, R. S., 1966 b. The acanthodian fishes of the Devonian Plattenkalk of the Paffrath Trough in the Rhineland. With an appendix containing a classification of the Acanthodii and a revision of the genus Homalacanthus”, Ark. Zool, 18, 147194.Google Scholar
Miles, R. S., 1966 c. “Protitanichthys, and some other coccosteomorph arthrodires from the Devonian of North America”, K. Svenska VetenskAkad. Handl, 10, 149.Google Scholar
Miles, R. S., 1967 a. “Observations on the ptyctodont fish, Rhamphodopsis, Watson”, J. Linn. Soc. (Zool.), 47, 99120.CrossRefGoogle Scholar
Miles, R. S., 1967 b. “Class Acanthodii and Class Placodermi”. In Harland, W. B. et al. : The Fossil record. Geol. Soc. London.Google Scholar
Miles, R. S., 1967 c. “The cervical joint and some aspects of the origin of the Placodermi”, Colloques Int. Cent. Natn., Rech. Scient., 163, 4971.Google Scholar
Miles, R. S., 1968 a. “A monograph of the Old Red Sandstone antiarchs of Scotland: Family Bothriolepididae”, Palaeont. Soc. (Monogr), 122, 1130.Google Scholar
Miles, R. S., 1968 b. “Jaw articulation and suspension in Acanthodes, and their significance”, Nobel Symposium, 4, 109127.Google Scholar
Miles, R. S. & Westoll, T. S., 1963. “Two new genera of coccosteid Arthrodira from the Middle Old Red Sandstone of Scotland, and their stratigraphical distribution”, Trans. Roy. Soc. Edinb., 65, 179210.CrossRefGoogle Scholar
Miles, R. S., 1968 a. “The placoderm fish Coccosteus cuspidatus, Miller ex Agassiz from the Middle Old Red Sandstone of Scotland. Part 1. Descriptive morphology”, Trans. Roy, Soc. Edinb., 67, 373476.CrossRefGoogle Scholar
Miles, R. S., 1968 b. “The placoderm fish Coccosteus cuspidatus, Miller ex Agassiz from the Middle Old Red Sandstone of Scotland. Part 2.” (Consulted in Manuscript).Google Scholar
Moy-Thomas, J. A., 1940. “The Devonian fish Palaeospondylus gunni, Traquair”, Phil. Trans. Roy. Soc, 230B, 391413.Google Scholar
Newberry, J. S., 1889. “The Paleozoic fishes of North America”, Monog. U. S. Geol. Surv., 16, 1340.Google Scholar
Nikolsky, G. V., 1963. The ecology of fishes. Academic Press, London.Google Scholar
Obruchev, D. V., 1927. “Angarichthys, neue Arthrodiren-Gattung aus dem Devon des Flusses Bachta (Sibirien)Izv. Geol. Kom., 45, 679692. (In Russian with German summary).Google Scholar
Obruchev, D. V., 1932. “Holonemidae des Russischen Devons”, Trav. Inst. Paleozool. Acad. Sci. U. R. S. S., 2, 97115.Google Scholar
Obruchev, D. V., 1964. “Class Placodermi”, In Obruchev, D. V.: Fundamentals of palaeontology. A manual for palaeontologists and geologists of the U.S.S.R., XI. Moscow. (In Russian).Google Scholar
Obruchev, D. V., 1967. “On the evolution of the Heterostraci”, Colloques Int. Cent. Natn. Rech. Scient., 163, 3747.Google Scholar
Obruchev, D. V. & Karatajūtė-Talimaa, V., 1967. “Vertebrate faunas and correlation of the Ludlovian-Lower Devonian in eastern Europe”, J. Linn. Soc. (Zool.), 47, 514.CrossRefGoogle Scholar
Obrucheva, O. P., 1962. Armoured fishes of the Devonian of the U.S.S.R. (Coccosteidae and Dinichthyidae). Moscow. (In Russian).Google Scholar
Ørvig, T., 1957. “Notes on some Palaeozoic lower vertebrates from Spitsbergen and North America”, Norsk, Geol. Tidsskr., 37, 285353.Google Scholar
Ørvig, T., 1960. “New finds of acanthodians, arthrodires, crossopterygians, ganoids and dipnoans in the Upper Middle Devonian Calcareous Flags (Oberer Plattenkalk) of the Bergisch Gladbach-Paffrath Trough. Pt. 1”, Paläont. Z., 34, 4960.CrossRefGoogle Scholar
Ørvig, T., 1962. “Y a-t-il une relation directs entre les arthrodires ptyctodontidesetlesholocephales?”, Colloques, Int. Cent. Natn. Rech. Scient., 104, 4961.Google Scholar
Ørvig, T., 1967. “Phylogeny of tooth tissues: evolution of some calcified tissues in early vertebrates”. In Miles, A. E. W.: Structural and chemical organizations of teeth. Academic Press, New York.Google Scholar
Ostrom, J. H., 1964. “A functional analysis of jaw mechanics in the dinosaur Triceratops”, Postilla, 88, 135.Google Scholar
Patterson, C., 1965. “The phylogeny of the chimaeroids”, Phil. Trans. Roy. Soc, 249B, 101219.Google Scholar
Patterson, C., 1967. “Class Selachii”, In Harland, W. B. et al. : The Fossil Record. Geol. Soc. London.Google Scholar
Philip, G. M. & Pedder, A. E. H., 1964. “A re-assessment of the age of the Middle Devonian of south-eastern Australia”, Nature, Lond., 202, 13231324.CrossRefGoogle Scholar
Romer, A. S., 1933. “Eurypterid influence on vertebrate history”, Science, N.Y., 78, 114117.CrossRefGoogle ScholarPubMed
Romer, A. S., 1955. “Fish origins—fresh or salt water?”, Deep Sea Res., 3, (Suppl.) Papers in marine biology and oceanography dedicated to Henry Bryant Bigelow, 261280.Google Scholar
Romer, A. S., 1966. Vertebrate palaeontology. 3rd ed. Univ. of Chicago Press.Google Scholar
Schaeffer, B., 1958. “Evolution in the subholostean fishes”, Evolution, N.Y., 10, 201212.CrossRefGoogle Scholar
Schaeffer, B., 1965. “The role of experimentation in the origin of higher levels of organization”, Syst. Zool., 14, 318336.CrossRefGoogle ScholarPubMed
Schaeffer, B., 1967. “Comments on elasmobranch evolution”. In Gilbert, P. W., Mathewson, R. F. & Rail, D. P.: Sharks, skates and rays. John Hopkins Press, Baltimore.Google Scholar
Schmidt, H., 1925. “Schwellen und Beckenfazies im ostrheinischen Palaeozoikum”, Z. Dt. Geol. Ges., 1925, 226234.Google Scholar
Schmidt, H., 1928. “Exkursionsbericht über die Exkursionen bei Wildungen”, Paläont., Z., 9, 58.Google Scholar
Simpson, G. G., 1953. The major features of evolution. Columbia Univ. Press, New York.CrossRefGoogle Scholar
Simpson, G. G., 1959. “The nature and origin of supraspecific taxa”, Cold Spring Harb. Symp. Quant. Biol., 24, 255271.CrossRefGoogle ScholarPubMed
Simpson, G. G., 1961. Principles of animal taxonomy. Columbia Univ. Press, New York.CrossRefGoogle Scholar
Skeels, M. A., 1962. “Two new fishes from the Middle Devonian Silica formation, Lucas County, Ohio”, J. Paleont, 36, 10391046.Google Scholar
Smith, B. G., 1937. “The anatomy of the Frilled Shark Chlamydoselachus anguineus, Garman”, Am. Mus. Nat., Hist., Bashford Dean Mem. Vol., 6, 335505.Google Scholar
Stensiö, E. A., 1925. “On the head of the macropetalichthyids with certain remarks on the head of the other arthrodires”, Publs Field. Mus. Nat. Hist. (Geol.), 4, 87197.Google Scholar
Stensiö, E. A., 1931. “Upper Devonian vertebrates from East Greenland, collected by the Danish Greenland expedition in 1929 and 1930”, Meddr Grenland, 96, no. 1, 1212.Google Scholar
Stensiö, E. A., 1934 a. “On the Placodermi of the Upper Devonian of East Greenland. 1. Phyllolepida and Arthrodira”, Meddr Grenland, 97, no. 1. 158.Google Scholar
Stensiö, E. A., 1934 b. “On the heads of certain arthrodires 1. Pholidosteus, Leiosteus, and acanthaspids”, K. Svenska, VetenskAkad. Handl, 13, 179.Google Scholar
Stensiö, E. A., 1936. “On the Placodermi of the Upper Devonian of East Greenland. Supplement to part 1”, Meddr, Grenland, 97, no. 2, 152.Google Scholar
Stensiö, E. A., 1939. “On the Placodermi of the Upper Devonian of East Greenland. 2nd Supplement to part 1”, Meddr Grenland, 97, no. 3, 133.Google Scholar
Stensiö, E. A., 1942. “On the snout of arthrodires”, K. Svenska VetenskAkad. Handl, 20, 132.Google Scholar
Stensiö, E. A., 1944. “Contributions to the knowledge of the vertebrate fauna of the Silurian and Devonian of western Podolia. 2. Notes on two Arthrodires from the Downtonian of Podolia”, Ark. Zool., 35A, 183.Google Scholar
Stensiö, E. A., 1945. “On the heads of certain arthrodires. 2. On the cranium and cervical joint of the Dolichothoraci (Acanthaspida)”, K. Svenska VetenskAkad. Handl., 22, 170.Google Scholar
Stensiö, E. A., 1947. “The sensory lines and dermal bones of the cheek in fishes and amphibians”, K. Svenska VetenskAkad. Handl., 24, 1195.Google Scholar
Stensiö, E. A., 1948. “On the placodermi of the Upper Devonian of East Greenland. 2. Antiarchi subfamily Bothrioepinae. With an attempt at a revision of the previously described species of that family”, Palaeozool., Groenland., 2, 1622.Google Scholar
Stensiö, E. A., 1950. “La cavité labrinthique, l'ossification sclérotique et l'orbite de Jagorina”, Colloques Int. Cent., Natn. Rech. Scient., 21, 941.Google Scholar
Stensiö, E. A., 1959. “On the pectoral fin and shoulder girdle of the arthrodires”, K. Svenska VetenskAkad. Handl., 8, 1229.Google Scholar
Stensiö, E. A., 1963. “Anatomical studies on the arthrodiran head. Pt. 1. Preface, geological and geographical distribution, the organisation of the arthrodires, the anatomy of the head in the Dolichothoraci, Coccosteomorphi and Pachyosteomorphi”, K. Svenska VetenskAkad. Handl., 9, 1419.Google Scholar
Stensiö, E. A. & Säve-Söderbergh, G., 1938. “Middle Devonian vertebrates from Canning Land and Wegener Peninsula (East Greenland). Pt. 1. Placodermi, Ichthyodorulithes”, Meddr Grenland, 96, no. 6, 138.Google Scholar
Stevens, M. S. ( = Skeels, M. A.), 1964. “Thoracic armour of a new arthrodire (Holonema), from the Devonian of Presque Isle County, Michigan”, Pap. Mich. Acad. Sci., 49, 163175.Google Scholar
Tchernavin, V. V., 1953. The feeding mechanism of a deep sea fish: Chauliodus sloani Schneider. Brit. Mus. (Nat. Hist.), London.Google Scholar
Traquair, R. H., 1898. “Notes on Palaeozoic fishes, No. II”, Ann. Mag. Nat. Hist., 11, 6770.CrossRefGoogle Scholar
Van Valen, L., 1963. “The head shield of Macropetalichthys, (Arthrodira)”, J. Paleont., 37, 257263.Google Scholar
Van Valen, L. & Sloan, R. E., 1966. “The extinction of the multituberculates”, Syst. Zool, 15, 261278.CrossRefGoogle Scholar
Von Wahlert, G., 1965. “The role of ecological factors in the origin of higher levels of organization”, Syst., Zool., 14, 288300.CrossRefGoogle ScholarPubMed
Waterston, C. D., 1954. “Catalogue of type and figured specimens of fossil fishes and amphibians in the Royal Scottish Museum, Edinburgh”, Trans. Edinb. Geol. Soc, 16, 190.CrossRefGoogle Scholar
Watson, D. M. S., 1934. “The interpretation of arthrodires”, Proc. Zool. Soc. Lond., 1934, 437464.CrossRefGoogle Scholar
Watson, D. M. S., 1937. “The acanthodian fishes”, Phil. Trans. Roy. Soc, 228B, 49146.Google Scholar
Watson, D. M. S., 1951. Palaeontology and modern biology. Yale Univ. Press, New Haven.Google Scholar
Watson, D. M. S., 1961. “Some additions to our knowledge of Antiarchi”, Palaeontology, 4, 210220.Google Scholar
Westoll, T. S., 1945. “The paired fins of placoderms”, Trans. Roy. Soc. Edinb., 61, 381398.CrossRefGoogle Scholar
Westoll, T. S., 1958 a. “The origin of continental vertebrate faunas”, Trans. Geol. Soc. Glasg., 23, 127.Google Scholar
Westoll, T. S., 1958 b. “The lateral fin-fold theory and the pectoral fins of ostracoderms and early fish”, In Westoll, T. S.: Studies on fossil vertebrates. Univ. London: Athlone Press.Google Scholar
Westoll, T. S., 1963. “The hyomandibular problem in placoderm fishes”, ContrdPap. 16th Int. Congr. Zool., 1, 176.Google Scholar
Westoll, T. S. 1967. “Radotina, and other tesserate fishes”, J. Linn. Soc. (Zool.), 47, 8398.CrossRefGoogle Scholar
Westoll, T. S. & Miles, R. S., 1962. “On an arctolepid fish from Gemünden”, Trans. Roy. Soc. Edinb., 65, 139153.CrossRefGoogle Scholar
White, E. I., 1952. “Australian arthrodires”, Bull Br. Mus. Nat. Hist., (Geol.), 1, 249304.Google Scholar
White, E. I., 1961. “The Old Red Sandstone of Brown Clee Hill and the adjacent area. II. Palaeontology”, Bull. Br., Mus. Nat. Hist., (Geol.), 5, 243310.Google Scholar
White, E. I., 1968. “Devonian fishes of the Mawson-Mutlock area, Victoria Land, Antartica”, Scient. Rep. Transantarct. Exped., 16, 126.Google Scholar
Woodward, A. S., 1924. “Un nouvel elasmobranche (Cratoselache pruvosti, gen. et sp. nov.) due calcaire carbonifère inférieur de Denée”, Liége Soc. Geol. Belg., Livre jubilaire, 5962.Google Scholar