LITERATURE CITED
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1918. Observations on the genus Lysorophus Cope. Ann. Mag. Nat. Hist., (9)2:232-239.
Bystrow, A. P.
1938. Dvinosaurus als neotenische Form der Stegocephalen. Acta Zool., 19:209-295.
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1935. Description of a collection of associated skeletons of Trimerorhachis. Contrib. Mus. Pal. Univ. Michigan, 4:227-274.
Cope, E. D.
1889. The Batrachia of North America. Bull. U. S. Nat. Mus., 34:1-525.
de Beer, G. R.
1937. The development of the vertebrate skull. Pp. xxiii + 552. Oxford, Clarendon Press.
de Villiers, C. G. S.
1934. Studies of the cranial anatomy of Ascaphus truei Stejneger, the American "Liopelmid." Bull. Mus. Comp. Zool., 77:1-38.
Emelianov, S. W.
1936. Die Morphologie der Tetrapodenrippen. Zool. Jahrb. (Anat.), 62:173-274.
Francis, E. T. B.
1934. The anatomy of the salamander. Pp. xxxi + 381. Oxford, Clarendon Press.
Gamble, D. L.
1922. The morphology of the ribs and the transverse processes of Necturus maculatus. Jour. Morph., 36:537-566.
Gray, P.
1930. On the attachments of the Urodele rib to the vertebra and their homologies with the capitulum and tuberculum of the Amniote rib. Proc. Zool. Soc. London, 1930(1931):907-911.
Gregory, J. T.
1950. Tetrapods from the Pennsylvanian nodules from Mazon Creek, Illinois. Am. Jour. Sci., 248:833-873.
Hecht, M. E.
1957. A case of parallel evolution in salamanders. Proc. Zool. Soc. Calcutta, Mookerjee Mem.:283-292.
Holmgren, N.
1933. On the origin of the tetrapod limb. Acta Zool., 14:185-295.
1939. Contributions to the question of the origin of the tetrapod limb. Acta Zool., 20:89-124.
1949a. Contributions to the question of the origin of tetrapods. Acta Zool., 30:459-484.
1949b. On the tetrapod limb problem again. Acta Zool., 30:485-508.
Herre, W.
1935. Die Schwanzlurche der mitteleocänen (oberlutetischen) Braunkohle des Geiseltales und die Phylogenie der Urodelen unter Einschluss der fossilen Formen. Zoologica, 33:87, 1-5.
Jarvik, E.
1942. On the structure of the snout of Crossopterygians and lower gnathostomes in general. Zool. Bidrag fran Upsala, 21:235-675. 1952. On the fish-like tail in the Ichthyostegid Stegocephalians. Meddelelser on Grønland, 114(12):1-90.
Mookerjee, H.K.
1930a. On the development of the vertebral column of the Urodela. Phil. Trans. Roy. Soc. London, B 218:415-446.
1930b. On the development of the vertebral column of the Anura. Philos. Trans. Royal Soc. London, B 219:165-196.
MacBride, E.W.
1932. Recent work on the development of the vertebral column. Cambridge, Biol. Rev., 7:108-148.
McDowell, S.B.
1958. Are the frogs specialized seymouriamorphs? (Abstract) Anat. Rec., 132(3):472.
Naef, A.
1929. Notizen zur Morphologie und Stammesgeschichte der Wirbeltiere. 15. Dreissig Thesen über Wirbelsäule und Rippen, insbesondere bei den Tetrapoden. Zool. Jahrb., 50:581-600.
Noble, G. K.
1922. The phylogeny of the Salientia; I. The osteology and the thigh musculature; their bearing on classification and phylogeny. Bull. Amer. Mus. Nat. Hist., 46:1-87.
1927. The value of life-history data in the study of the evolution of the Amphibia. Annals New York Acad. Sci., 30:31-128.
Piveteau, J.
1937. Un Amphibien du Trias inférieur. Essai sur l'origine et l'évolution des Amphibiens Anoures. Annales de Paléontologie, 26:135-176.
1955. Anoura. In: Traité de Paléontologie, 5:250-274. J. Piveteau, Masson et Cie, Paris.
Pusey, H. K.
1943. On the head of the liopelmid frog, Ascaphus truei. I. The chondrocranium, jaws, arches, and muscles of a partly grown larva. Quart. Jour. Micr. Sci., 84:105-185.
Reed, H. D.
1915. The sound-transmitting apparatus in Necturus. Anat. Rec., 9:581-590.
Remane, A.
1936. Wirbelsäule und ihre Abkömmlinge. In: Handbuch der vergleichenden Anatomie der Wirbeltiere, L. Bolk et al., 4:1-206. Urban and Schwarzenberg, Berlin, Vienna.
Ritland, R. M.
1955a. Studies on the post-cranial morphology of Ascaphus truei. I. Skeleton and spinal nerves. Jour. Morph., 97:119-174.
1955b. Studies on the post-cranial morphology of Ascaphus truei. II. Myology. Jour. Morph., 97:215-282.
Romer, A. S.
1945. Vertebrate paleontology. 2nd edition. Pp. viii + 687. Univ. Chicago Press.
1947. Review of the Labyrinthodontia. Bull. Mus. Comp. Zool., 99:3-368.
Säve-Söderbergh, G.
1934. Some points of view concerning the evolution of the vertebrates and the classification of this group. Arkiv för Zoologi, 26A:1-20.
Stadtmüller, F.
1936. Kranium und Visceralskelett der Stegocephalen und Amphibien. In: Handbuch der vergleichenden Anatomie der Wirbeltiere, by L. Bolk et al., 4:501-698.
Stephenson, N. G.
1955. On the development of the frog, Leiopelma hochstetteri Fitzinger. Proc. Zool. Soc. London, 124(4):785-795.
Stipanicic, P. N. and Reig, O. A.
1955. Breve noticia sobre el hallazgo de anuros en el denominado "Complejo Porfirico de la Patagonia Extraandina," con consideraciones acerca de la composicion geologica del mismo. Revista de la Asoc. Geol. Argentina, 10(4):215-233.
1956. El "complejo porfirico de la Patagonia extraandina" y su fauna de Anuros. Acta Geol. Lilloana (Univ. Nac. del Tucuman), 1:185-297.
Sushkin, P. P.
1936. Notes on the pro-Jurassic Tetrapoda from U. S. S. R. III. Dvinosaurus Amalitzky, a perennibranchiate stegocephalian from the Upper Permian of North Dvina. Trav. Inst. Pal. Acad. Sci. URSS, 5:43-91.
Watson, D. M. S.
1940. The origin of frogs. Trans. Roy. Soc. Edinburgh, 40(7):195-231.
Transmitted April 7, 1959.