20 Bulletin American Museum of Natural History. [Vol. XIX, 



bra agrees in size with the basioccipital of some skulls of 

 Protosphyrcena. It is possible that it belongs to either 

 Pachyrhizodus or Anogmius, but it appears to be different. 

 Cope believed (Proc. Amer. Assoc. Adv. Sci., XXVI, 1878, 

 p. 299) that this genus possessed well developed vertebrae, but 

 whether or not he based his opinion on this particular verte- 

 bra is not known. It is very desirable that collectors shall 

 give attention to the finding of such parts of the body of the 

 fishes of this genus as have not yet been described; and such 

 parts include practically all parts behind the shoulder girdle 

 and pectoral fins. 



Protosphyraena sequax, sp. nov. 



ProtosphyrcBna nitida Felix (J.), Zeitschr. deutsch. geol. Gesellsch. 

 XLII, 1890, p. 278, pi. xii, figs. 1-3; pi. xiii, figs, i-ab; pi. xiv, 

 figs. 2-7. — LooMis (F. B.), Palceontogr. XLVI, 1900, p. 227 (in 

 part). — Hay (O. P.), Bibliog. and Cat. Foss. Vert. N. A. 1902, 

 P- 379 (in part). 



Dr. Loomis has already concluded that, on account of the 

 position of the teeth of the dentary bone, Felix's specimen 

 does not belong to the same species as the dentary figured by 

 Cope as part of P. nitida; but Loomis 's explanation is that 

 Cope's dentary does not belong with the premaxillary, and 

 is, therefore, not a part of P. nitida, an idea already sug- 

 gested by Felix {op. cit.). As elsewhere remarked, there is 

 no reason for questioning the unity of Cope's type. The 

 more reasonable explanation is that Felix's specimen does 

 not belong to Cope's species, P. nitida. And one of the 

 grounds for this conclusion is found in the fact that the 

 teeth of the maxillae and those of the dentary, except 

 the three anterior fangs, are, in Felix's specimen, inserted 

 at nearly right angles to the containing bones. Even those 

 of the premaxillae emerge nearly perpendicular to the border 

 of the latter bone. 



Nor can Felix's specimen belong to P. dimidiata. The 

 posterior teeth of the maxilla of the type of the latter have a 

 decided slant forward. The median and anterior teeth are 

 nearly perpendicular. All the teeth of the premaxilla appear 



