TAB. VIII. 



Fig. 

 1. 



2. 

 3. 



4. 

 5. 



6, 6 a. 



7, 7 a, b. 



8, 8 a, b. 



9, 9 a, b, c. 



Pachyrisma grande, anterior view, p. 79. 



posterior view, showing ligamental area, p. 79. 

 hinge area of right valve, p. 79. 



hinge area of left valve, p. 79. 



side view, p. 79. 



Unicardium parvulum, p. 74. 

 varicosum, p. 73. 

 nucleus of ditto, p. 73. 



impressum, p. 73. 



