276 PROCEEDINGS OF THE NATIONAL MUSEUM vol. los 



holotype of H. hesperius (USNM 8713) and that of C. sienodinus were 

 both collected by T. E. Willard of the U. S. Geological Survey on 

 Sept. 14, 1914, from the same exposure of Fox Hills sandstone in sec. 

 23, T. 4 N., R. 67 W., southwest of Milliken, Weld County, Colo. It 

 is concluded that Cyclolepis sienodinus is a synonym of Hemilampro- 

 nites hesperius. 



Cockerell (1919) referred Hemilamproiiites hesperius to the Hemi- 

 ramphidae. Such a relationship is indeed supported by the centrally 

 lobate basal border and the marked angle of meeting of the apical 

 and basal circuli displayed by the scales. As remarked by David 

 (1946) in another case, however, the proportionately long, broadly 

 rounded outline and lack of discrete basal radii suggest relationship 

 also with either or both the Scomberesocidae and Exocoetidae, among 

 other Synentognathi. This distinctive combination of structural fea- 

 tures, which serves adequately to separate the Cretaceous species 

 from the Tertiary and living members of the order, may well indicate 

 a primitive ancestral type. Unfortunately, the fossil record of the 

 flying fishes and their allies is meager. Until available information 

 permits reconstruction of the evolution of the order, no precise desig- 

 nation of the relationships of H. hesperius seems feasible. 



References 



Agassiz, L. 



1844. Recherche sur les poissons fossiles. Vol. 5, pt. 2, p. 103. 

 Cobban, W. A., and Reeside, J. B., Jr. 



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 Cockerell, T. D. A. 



1919. Some American Cretaceous fish scales. U. S. Geol. Surv. Prof. Pap. 

 120, pp. 165-188, pis. 31-37. 

 Cope, E. D. 



1871. On the fossil reptiles and fishes of the Cretaceous rocks of Kansas. 

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Bull. U. S. Geol. Geog. Surv., vol. 3 (art. 29), pp. 565-597, 5 pis. 

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1942. Description of fossil fishes from the upper Cretaceous of North 



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