PLATE XXIX 
Figs. 1 A, B, C. Amx>liicyrtoceras orcas (Hall). A, ventral view. B, 
lateral view showing the septa. C, two cross-sections, one taken at the 
base of the living chamber, the other 5 camerae lower. From Waukesha, 
Wisconsin; in the Racine member of the Niagaran. Type, numbered 2112, 
in the American Museum of Natural History. Same specimen as in 20th 
Rep. New York State Mus. Nat. Hist., 1868, pi. 17, figs. 1, 2. 
Figs. 2 A, B, C. Amphicyrtoceras tantalum Foerste. A, ventral view. 
B, lateral view. C, two cross-sections, one at base of living chamber, the 
other at base of specimen. From railroad quarry in northeastern edge 
of Hillsboro, Ohio; from the Cedarville member of the Niagaran. 
