PLATE VIII. 



Ortiionota venusta (page 129). 



Figure 1. Left valve, 



Ortiionota ixcerta (page 130). 



Figure 2. Right valve. 



Ortiionota speciosa (page 130). 



Figure 3, Right valve. 

 " 3#. Imperfect left valve ? 



Ortiionota simulans (page 131). 



Figure. 4, Left valve. 



Ortiionota angulifera ? (page 132). 



Figure 13; Fragment of left valve. The notch in front of the beak is due to dis- 

 t«rtion. 



" 13a. Right valve copied from McCoy, for comparison. 



MoDiOLOPSis ExiLis (page 132). 



Figure s. A small right valve. 

 " 5a. A large specimen. 



MoDiOLOPSis ruda (page 133). 



Figure G. Left valve. 



GcNIOPIIORA TRANSIENS (pagc 134). 

 Figure 7. Right valve. 



GoNiopHORA coNSiMiLis (page 135). 



Figure 8. Left valve. 



GoNiopiiORA BELLULA (page 136), 



Figure 9. Right valve. 



Cytherodon ? PLACiDus (page 137). 



Figure 10. Right valve, a cast shewing the impression of the teeth. 

 Figure 11. A variety. 



Cytiiekodon ? sociALis (lage 138). 



Figure 12. A specimen with the two valves in conncctiou. 



