SECTION V. 



CEPHALOPODA OF THE CRETACEOUS MABLS OF NEW JEBSEY. 



Class CEPHALOPODA. 



Order TETRABRANCHIATA. 



Family NAUTILID^. 



Genus NAUTILUS Breyn. 



Nautilus Dekayi. 



Plate XXXVII, Fig. 1-6; and Plate xxxviii, Figs. 1-4. 



Nautilus Dekayi Morton: Synopsis, p. 33, PI. viii. Fig. 4, and PI. xiii, Fig. 4; 

 Gabb, Synopsis, p. 30; Proc. Acad. Nat. Sci., Phila., 1876, p. 277; Meek, 

 Check List, p. 25; Geol. Sur. N. J., 1868, p. 731; Invert. Paleont., vol. 9, 

 U. S. Geol. Surv. Terr., p. 496; Meek & Hayden, Proc. Acad. Nat. Sci., 

 Phila., vol. 8, p. 280; Hall & Meek, Mem. Am. Acad. Arts and Sci, Boston, 

 vol. 5, new ser., p. 406; Conrad, Jour. Acad. Nat. Sci., Phila., vol. 4, new 

 ser., p. 276. 



Shell of medium size, strongly subglobose in general form. In the 

 condition of casts, that in which it is usually found in New Jersey, it is 

 slightly umbilicate, but in the shell the axis is solid and somewhat extended 

 laterally from the body of the volution, so that the posterior margin of the 

 aperture is straightened on each side of the involved inner whorl, and as 

 seen from the back of the shell presents a strongly auriculate feature, like 

 that of a globular BelleropJion. Section of the volution from the umbilicus 

 outward more than semicircular, and the umbilical region impressed in the 

 shell, or somewhat funnel-formed in the cast; aperture large, transverse, 

 nearly twice as wide as long measured from the involved volution, which 



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