EXPLANATION OF PLATES. 449 



^[QURE. PAGE. 



18. Waldheimia australis, Dorsal valve. J, cardinal pro- 



cess ; t' , dental sockets; p^ hinge-plate ; s, septum ; c, 

 crura of the loop ; Z, reflected portion of the loop ; m, 

 quadruple adductor impression, .... 309 



19. Waldheimia australis, Ventral valve. /, foramen ; d, 



deltidium ; ^, teeth ; a, single muscular impression ; r, 

 cardinal muscles ; x, accessor}^ muscles ; p, pedicle- 

 muscles ; u, position of the vent ; z, attachment of 

 pedicle-sheath, ........ 309 



20-22. Waldheimia flavescens, Lam. Recent ; Australia. . 309 

 28. Waldheimia (Zeilleria) lagenalis, Schloth. Cornbrash, 



Rushdon, England, ....... 309 



Plate 135. 



24. Waldheimia (Aulaeothyris) resupinata, Sowb. Mid. 



Lias ; Ilminster, England, ...... 309 



25, 26. Centronella glans-fagea, Hall. Devonian ; Erie Co., 



N. Y., 310 



27. Rensellaeria ovoides, Hall. Devonian; N. Y., . . 310 



28, 29. Terebratella Magellanica, Chemn. Cape Horn, . 311 

 30-32. Terebratella (Trigonosemus) elegans,Konig. Cret. ; 



Eur., 311 



33. Terebratella (Trigonosemus) Palissii, Wood. Cret. ; 



Belgium, . . . . . . . . .31 



34, 35. Terebratella (Lyra) lyra, Sowb. Upper Greensand; 



England, 311 



36. Terebratella (Lyra) neocomiensis, Orb. L. Cret. ; 



Morteau, . . . . . . . , .311 



3T-39. Terebratella (Megerlea) truncata, Lam. Mediter., 311 

 40. Terebratella (Laqueus)Californica, Koch. Recent; Cal., 312 

 43, 44. Terebratella (Kingena) lima, Defrance. Chalk; 

 England. ^, dental sockets ; j, cardinal process ; c, 

 crura; d^ diverging processes of loop; ?-, reflected 

 portion; e, third attachment of loop; s, dorsal septum, 312 

 45-47. Bouchardia tulipa, Blainv. Brazil. /", foramen; a, 

 adductor impression; Z, loop; (i, deltidium; r, cardinal 

 muscles; t^ teeth; p, flg. 47, pedicle-muscles, fig. 46, 

 hinge plate; s, septum, . .... 312 



48, 49. Magas pumila, Sowb. {. Cret.; France, . . 312 



50-52. Platidea anomioides, Scacchi. Mediterranean Sea, . 312 



53, 54. Kraussina rubra, Pallas. So. Africa, . . . 313 



55, 56. Stringocephalus Burtini, Defrance. Dev. ; Europe. 



a, adductor ; c, crura ; Z, loop ; J, cardinal process ; 



p, hinge-plate; s, dorsal septum; v s', ventral septum; 



t, dental sockets, . . . . . . .313 



