14 U.S. NATIONAL MUSEUM BULLETIN 262 



Aphetoceras — Continued 



subcostulatum- -Continued 



Unklesbay, A, G., 1961: p. 377, pi. 52, fig. 1. 

 Hypotype 143006 



Jefferson City equivalent 

 (? Honey cut Fm.) Missouri 



subcostulatum ? Ulrich, Foerste, Miller, and Unkesbay 



Ulrich, E. O., et al., 1942: p. 23, 24, pi. 3, fig. 3. 

 Figured specimen 101337 



Cotter Fm. Missouri 



Described specimen 101339 



Jefferson City Fm. Missouri 



spp. 



Ulrich, E. O., et al., 1942: p. 24, 25, pi. 4, figs. 1, 2. 

 Figured specimen 101340 



Jefferson City Fm. Missouri 



Figured specimen 101341 



Jefferson City Horiz. ? Virginia 



Arkoceras 



exiguum Ulrich, Foerste, Miller, and Furnish 



Ulrich, E. O., et al., 1942: p. 69, pi. 12, figs. 3-5; pi. 43, figs. 1, 2; 



text-fig. 17d. 

 Syntypes 101406 



Smithville Ls. Arkansas 



sp. 



Ulrich, E. O., et al., 1942: p. 69. 



Described specimen 101407 



Naylor Ledge Ls. Quebec, Canada 



Armenoceras 



asiaticum Endo 



Endo, Riuji, 1932: p. 81, 82, pi. 16, figs. 2-6. 



Syntypes 83708, 83709 



Ssuyen Fm. Manchuria, China 



bassleri Endo 



Endo, Riuji, 1932: p. 82, pi. 22, figs. 5, 6; pi. 40, fig. 12. 



Holotype 83759 



Ssuyen Fm. Manchuria, China 



