SHOKTER ARTICLES AND DISCUSSION 



EUROPEAN FOSSIL FISH-SCALES 

 In European Cretaceous deposits fish-scales have been found 

 at various times, and occasionally have been named and described 

 by paleontologists. Dr. A. S. Woodward, in his great "Cata- 

 logue of the Fossil Fishes," has carefully and accurately listed 

 all the names so given, but has made little or no attempt to ex- 

 amine the records critically, assuming that they were valueless, 

 or nearly so. More recent work ori fish-scales brings out the fact 

 that these materials are of great value for the understanding of 

 Mesozoic fish life, but unfortunately they have been described 

 with little knowledge of their significant characters. An im- 

 portant pioneer work was that of Geinitz,^ describing scales from 

 the Turonian of Saxony. Geinitz realized that it was necessary 

 to make comparisons with scales of recent fishes, and gave a plate 

 of "Schuppen von lebenden Fischen," but unfortunately chose 

 species which had little relationship, for the most part, with the 

 fossils studied. The three plates of fossil scales appear to have 

 been very carefully drawn, and from them it is possible to gather 

 a number of facts not brought out in the text. Cyclolepis agas- 

 sizi appears to be Salmonoid, agreeing quite well with the modern 

 Salmo. Aspidolepis steinlai is like the scales of living Stroma- 

 teidae, as Poronotus. Osnieroides divaricatus evidently has 

 nothing to do with the genus to which it is assigned, but is of 

 characteristic Albulid type. Osmcroides leivesiensis (Mantell), 

 as determined by Geinitz, consists in the main of scales agreeing 

 with those of the remarkable living genus Pterothrissus. The 

 genus Cladocyclus presents some serious difficulties. The type 

 is a Brazilian species (C. gardneri Agassiz) from the Upper Cre- 

 taceous of the Province of Ceara. I am indebted to Dr. D. S. 

 Jordan for material referred to this species, and it appears that 

 the large scales have extremely fine circuli, while those of the 

 lateral line possess branching canals of the same general type as 

 those of the living S. American genus Ilydrolycus.^ It does not 

 »"Die Fossilen Fischsehuppen aus dem PlHnerkalke in Strehlen." 1868. 

 2 These canals are in the aptcoZ, not the basal field, as erroneously stated 

 by me in Annals Carnegie Museum, IX, p. 110. 



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