UllACmOl'ODA. 



f)? 



front sli;.'litly elevated ; sides de|)ie^se(l ; heiik short, tiipeniij^; 

 foruineii larj^e, iiieoinplete; deUidiii large, sepaiute ; loop .small. 

 mniular. Lon. 10, lat. 10, alt. 4 lines. 



Terebratida snhstriata, Schl. 1820, Petr. p. 2S:i. 



Bitch, Tcr. (iO. 



D'Orb. Prod. i. p. 377. 



Qiu'iist. llamlb. p. M')\. t.37. f- r>, 7- 

 Terebnitula striatula, Zieten, IH.'JO, WWrt. p. 59. pi. 44. f. 2 (not 



M(tiitt'U). 

 Terebratulina substriata, Davidson, Ann. Nat. Hist. 

 Fossil. Oxford CUiy. France j Germany. 



3. WALDIIEIMl.V. 



Shell : foramen complete ; loop elongated and reflected ; me- 

 dian septum of the smaller valve elongated. 



Waldheimia faustralis), King, 1^49, Permian Fossils, p. Si. 

 Terebratuhc with long loops, Dav. 1862, Ann. Xat. Hist. ]>. '6i'A. 

 Terebratulffi cinctie et cjirinata; (part.), Buck. 



The extent of the septum may be readily ascertained in fossil 

 species by a little acid, without injuring the specimens. 



The sections iuto which IValdheimia has been grouped depend 

 entirely upou mocUticatious of external form. 



\ Va Idheim ia fiatescens , 

 Fig. 'J. Fig. 7. 



Fie. 6. — Interior of dorsal valve with the animal. 



Fig. 7. — Section of both valves with the animal ; the muscles of the peduncle arc 

 not represented. 



«, «'. adductor muscle ; /. retractor muscle ; p. peduncle ; /. cardinal ])r<ice!-s ; 

 t. dental sockets ; >n. mouth ; t>. position of intestine. 



Db 



