PLATE XXni. 



Page. 

 Cyrena securis Meek 101 



Fig. 1. Left valve. 



Nat. Mus. Cat. Invert. Foss., 22884. 



2. Hinge of same. 



3. Right valve of specimen from southern Utah believed to belong to 



this species. 

 Nat. Mus. Cat. Invert. Foss., 22885. 



Cyrena sp 102 



Fig. 4. Right valve associated with specimen represented by Fig. 3. 

 Nat. Mus. Cat. Invert. Foss., 22886. 

 Veniella goniophora Meek 105 



Fig. 5. Right side view of an internal cast (after Meek). 



Veniella mortoni M. & H 104 



Nat. Mus. Cat. Invert. Foss., 22887. 

 Fig. 6. A small left valve. 



7. A small right valve. 



8. A large left valve. 



9. Hinge of same. 



238 



