标题：Studies on the Paleozoic selachian genus Ctenacanthus Agassiz. No. 2, Bythiacanthus St. John and Worthen, Amelacanthus, new genus, Eunemacanthus St. John and Worthen, Sphenacanthus Agassiz, and Wodnika Münster. American Museum novitates ; no. 2722
摘要："Some of the finspines originally referred to Ctenacanthus are reassigned to other taxa. Several characteristically tuberculate lower Carboniferous finspines are referred to Bythiacanthus St. John and Worthen, including one of Agassiz's original species, Ctenacanthus brevis. Finspines referable to Bythiacanthus are known from western Europe, the U.S.S.R., and North America. Amelacanthus, new genus, is described on the basis of finspines from the United Kingdom. Four species are recognized, two of which were originally assigned to Onchus by Agassiz, and all four of which were referred to Ctenacanthus by Davis. Eunemacanthus St. John and Worthen is revised to include some European and North American species. Sphenacanthus Agassiz is shown to be a distinct taxon from Ctenacanthus Agassiz, on the basis of finspine morphology, and its widespread occurrence in the Carboniferous of North America is demonstrated. Similarities are noted between the finspines of Sphenacanthus and Wodnika, and both taxa are placed provisionally in the family Sphenacanthidae. A new species of Wodnika, W. borealis, is recognized on the basis of a finspine from the Permian of Alaska"--P. [1].
