I^LA-TE 6. 



Page,' 

 Fig. 1. Placenticeras ? Vancouverensis; dorsal view, redaced fco about two- 

 thirds the natural diameter 370 



1 a. Lateral view of same. 



1 1). Septum of same, enlarged to 3 diameters. 



1 c. A section of one of the whorls. 



Fig. 2. Nautilus Campbelli ; anterior view, reduced to about two-thirds the 



natural diameter - 373 



2 a. Lateral view of same. 



Fig. 3. An outline section of one of the whorls of Nautilus Dekayi, taken from 

 Dr. Morton's original specimen ; reduced to about two-thirds the 

 natural diameter. 



