STANTON : THE MARINE CRETACEOUS INVERTEBRATES. 



EXPLANATION OF PLATE II. 



PAGE 



OSTREA TARDENSIS Stanton . . ... . . . . . . ii 



Fig. i. Exterior of more strongly curved upper valve. Natural size. 

 Fig. 2. Interior of same. 



NOTE. This specimen was inadvertently posed with the beak downward. 



(VOL. iv) 



