EXPLANATION OF PLATE CIX. 



BELEMNITELLA AMERICANA (Morton), p. 839 



1. Ventral view of a large individual showing the slit. 



2. Another view of the same individual with a section removed 



to show the alveolar cavity. 



3. View of a smaller individual preserving the mucronat? ex- 



tremity. 



Navcsink marl; Holmdel. 



4. View of a cast of the alveolar cavity. 



Navesink marl; Atlantic Highlands, (108). 



BACULITES OVATUS Say, p. 821 



5. Lateral view of an internal cast. 



Navesink marl; Atlantic Highlands, (108). 



BACULITES ASPER Morton ?, p. 823 



6-7. Two views of a specimen identified and illustrated by Whit- 

 field. 



Navssink marl; Holmdel. 



1 102 



