PLATE 9. 



Page. 



Fig. 1. Ostrea Ci wgesta 13 



1, a. A lateral view of a lower valve, growing on others, with its sides ascending nearly ver- 

 tically. 

 1, 6. Several lower valves partly imbedded in the marly rock, showing their truncated origi- 

 nally attached ends or bases, with lateral walls produced so as to present the appear- 

 ance of short cylindrical tubes ; also internal views of some upper valves. 

 ], c. Internal views of lower valves, growing on fragments of the outer-shell layer of Inocera- 

 mus, showing the appearance of this valve before its lateral margins had grown so 

 as to rise much above the surface of attachment. 

 1, d. Internal view of one of the lower valves, somewhat magnified. 



1, e and/. Upper valves ; the latter magnified, and showing very faint traces of radiating 

 markings very rarely seen on the inner surface. 



Fig. 2. Anomia? obliqua 22 



An upper valve (if really an Anomia) of the type-specimen. 



FlG. 3. INOCERAMUS PROBLEMATICUS G2 



3, a. A left view of a small ovate specimen. 

 3, h. A right view of an elongated specimen. 



Fig. 1. Inoceramus problematic i's, var. avtccloides 63 



An internal cast of a right valve of the type of the var. 



