12 GAN IB OS OO II 
PLACENTICERAS PLANUM Hyatt. 
(Page 202. ) 
Fie. 1. Side view of the small specimen represented by Pl. XX XIII, fig. 4. 
2, 3. Aperture and side views of a larger specimen. 
San Carlos, Presidio County, Tex.; San Carlos beds, Upper Cretaceous; Coll. U. S. Geol. Survey. 
320 
