1903.] Hay, North American Cretaceous Fishes. 8 1 



suggest that they were hinged ; as Cope also inferred from the 



form of the alveolar fossae. This author has described the 



tips of the teeth as being simple; but in the case of some of 



them I find the peculiar spade-shaped 



apices which Cope has described in 



the case of 5. apicalis. Fig. 68 shows 



two of the caudal vertebrse. They 



are much like those of Enipo, but 



lack the longitudinal ribs of that Fig. es. suatoc^us oxypogon 



genus. Under the lens, however, a TXcaudaTvlrtebrae.^idevilw.^^' 



fine longitudinal striation is seen on 



the sides of the centra. Dr. Woodward has placed this genus 



in the Dercetidae, but notwithstanding the union of the pari- 



etals in the midline, it appears to the writer to belong to the 



Enchodontidae. 



Empo Cope 



This genus was erected by Cope in 1872 (Proc. Amer. 

 Philos. Soc, XII, p. 347). The type species is E. nepaholica, 

 later emended by Cope to nepcBolica. The species belonging to 

 this genus have been referred by Loomis (Palaeontogr., XL VI, 

 1900, p. 267) to CimoUchthys; and Dr. A. S. Woodward has 

 more recently (Cat. Foss. Fishes, IV, p. 221) adopted the 

 same course. That the two genera are not identical the 

 present writer will not affirm ; but the type species of CimoUch- 

 thys, C. levesicnsis, is, as Dr. Woodward has said, not satis- 

 factorily definable, many parts of the skull not being known. 

 Likewise, we are in ignorance regarding various structures of 

 Empo. It is therefore not at all improbable that differences 

 of generic importance may yet be discovered in these types. 

 It is as well to be conservative in suppressing genera as in 

 establishing them. For these reasons the writer prefers to 

 retain Empo. 



Empo nepaholica Cope. 



Pl. I. Fig. 4. 



Empo nepaholica Cope (E. D.), Proc. Amer. Philos. Soc. XII, 1872, 

 p. 347; Rep't U. S. Geol. Surv. Mont. etc. 5th Ann. Rep't, 1872, 

 p. 345. — Hay (O. p.), Bibliog. and Cat. Foss. Vert. N. A. 1902, 

 p. 387. 



[yanuary, /goj.] 6 



