EXPLANATION OF THE PLATES. 537 



PLATE XYm. 



* The figures marked are left valves. 



Tfnionidee. 



Page 



1. "Dnio littoralis, Drap. \. Auvergne 433 



2. {Monocondylaa) Paraguayanus, D'Orb. |. S. America 434 



3. Castalia ambigua, Lam. ^. E. Amazon : 434 



4. Hyria syrmatophora, Gronov. f . S. Americaf 434 



5. *L:i(iiiia exotica, Lam. ■§-. Africa, R. Nile 435 



6. Mycetopus soleniformis, D'Orb. i. S. America, R. Parana 435 



7. -ffitheria semilunata, Lam. \. Senegal 435 



ChamidcB. 



8. Chama macropbylla, Cbemn. |-. AntOIes 437 



9, left valve 437 



10. Diceras arietinum. Lam. \. Coral Oolite, France 439 



11. left valve 439 



12. {Reqicienia) Lonsdalii, J. Sby. \. Neocomian, Spain 



—Brit , 439 



HippiiritidcB. 

 23. Caprotina striata, D'Orb. U. Greensand, France 451 



14. left valve 451 



TridacnidcB. 



15. Tridacna squamosa, Cbem. i. Bombay 452 



16. Hippopus maculatus. Lam. \. N. Australia 453 



Cardiadce (part). 



17. Lithocardium aviculare. Lam. \. Eocene, Paris 454 



Cyprinidce (part). 



18. Cardilia semi-sulcata, Lam. Amboina 469 



19 ♦Megalodon cucullatus, J. Sby. \. Devonian, Eifel 469 



•j The animal of Hyria has two siphonal orilicea. 



