MOLLUSCA. 817 



Family NAUTILIDAB. 



Genus Nautii,us Linneus. 



Nautilus dekayi Morton. 



Plate C, Figs. 1-5. 



1833. Nautilus Dekayi Mort., Am. Jour. Sci., ist ser., vol. 23, 



p. 291, pi. 8, fig. 4. 



1834. Nmitilus Dekayi Mort., Synop. Org. Rem. Cret. Gr. U. 



S., p. 33, pi. 8, fig. 4, pi. 13, fig. 4. 

 1856. Nautilws Dekayi Meek & Hayden, Proc. Acad. Nat. Sci. 



Phil., vol. 8, p. 280. 

 1859. Nautilus Dekayi Meek, Northwest Terr., Rep. Prog. 



Assin. and Saskat. Expl. Exped., H. Y. Hind, p. 185, 



pi. 2, figs. 9-10. 

 1861. Nautilus Dekayi Gabb, Synop. Moll. Cret. Form., p. 86 



(30). 

 1864. Nautilus Dekayi Meek, Check List Inv. Foss. N, A., 



Cret. and Jur., p. 25. 

 1868. Nautilus Dekayi Con., Cook's Geol. N. J., p. 731. 

 1876. Nautilus Dekayi Gabb, Proc. Acad. Nat. Sci. Phil., 1876, 



p. 277. 

 1876. Nautilus Dekayi Meek, Rep. Inv. Cret. and Ter. Foss., 



Up. Mo., p. 496, pi. 27, figs. la-e. 

 1892. Nautilus Dekayi Whitf., Pal. N. J., vol. 2 (Monog. U. S. 



G. S., vol. 18), p. 243, pi. 37, figs. 1-6, pi. 38, figs. 1-4. 

 1894. Butrephoceras Dekayi Hyatt, Proc. Am. Phil. Soc, vol. 



32, P- 555, Pl- i3> figs. 4-8, pi. 14, fig. I. 

 1905. Butrephoceras dekayi Johns., Proc. Acad. Nat. Sci. Phil., 



1905, p. 28. 



Description. — '"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 iti the shell 

 the axis is solid and somewhat extended laterally from the body 

 of the volution, so that the posterior margin of the aperture 



52 PAI, 



