EXPLANATION OF PLATE L 



Fig. 1. Cantharus? julesburgensis; lateral view. 

 "2. " " aperlural view. 



" 3. Luciua cleburui; right-side view. 

 " 4. " " dorsal view. 



" 5. Lucina profunda; right valve. 

 " 6. " " left valve. 



" 7. Pteria (Oxytoma) erecta; right valve. 



8. '• " " left valve. 



" 9. Solemya bilix; right valve. 



" 10. Callianassa ulrichi ; leftmamis; exterior view. 

 " 11. " " " iuterior view. 



" 12. Tubulostium dickhauti ; lateral view. 

 "13. " " peripheral view. 



All of natural size. 



