EXTLANATTON OF PT.ATl- I.XITI. 



'TenF.a tartlts Coiirail p. 572 



\~2. The iiitL-nial cast of a left \alvc and a ijlaslcr cast from the 

 natural nirmld i if the exterior of the same. 

 3. The internal east of a more o\'ate left valve. 

 IVooJhiiry clay: Lnrillanl. {T02). 

 4-5. I.ateral and anterior \ie\vs nf an internal cast. 

 Xaz'CsiiiL' iiiiii'L 



6. Lateral \ievv of a small internal cast eif a left valve. 



Red BaiiL- sand: Slirrwshiiry Kivcr iii'j). 



Texe.\ I'Ixguis Conrad p. 57'-t 



7. Lateral view eif an internal cast. (x_'l. 



Xii'Z\-si/(lc intirl. near U'alii f.'iil (;/5'). 



C.MiDifAt XM/cr.roi.rs 1 \\ hilheld ) p. 575 



X-o. Lateral and cardnial view of the Ivpe S]ieeinien, ( X2 ) . 

 (After Wdlitfield, I 



Maiiusqiuiii marl: l-aninif^ilali. 



C.\Ri)iuit WEX'ox'AH n. sp p. 576 



ID. Lateral view of a idgiit valve. 

 11-12. Lateral and posterior \-iews nf ,a ciiinidete specimen. 

 13. Literif.ir of a right v.al\"e. 



Corsicaiia, Texas. V. S. Xat. Mas. Cull. No. 20.^)27. 

 14-lrt. Lateral views (A the internal casts cif three ri.ght valves. 

 W'caoual; sand: near Marlhrnn, (/^o). 



Cardiuim Er'EAUi.EXSis Conrad p. 577 



17-1S. External and internal views of a left \al\-e. 



Union Co. Miss.. C. S. Nat. Mns. Coll. No. 20,817. 



19. The internal cast of a right valve. 



20. Squeeze taken from a natural mould i.if the exterior. 



ll'enonali sand: near Craiefords Corner, (126'). 



CvRtiirM LOXGSTREETI n. Sp. p. 579 



_'i. The internal cast of a left valve. 



22. Squeeze taken frcnii the natural mould iif ihe exterior rif the 

 same. 



Wenoiiali sand: near Ci'aiefoi'ds Corner, (126'). 



lOoS 



