CONTENTS. 



Page. 



Letter of transmittal 405 



Introductory remarks 411 



Annotated and illustrated catalogue 420 



Conchifera 420 



OstreidtB 420 



Anomiidaa 421 



Mytilidae 423 



Unionidse 424 



Cyrenidae 435 



PisidiidsB 440 



Corbulidae 441 



Gasteropoda ~. 443 



Auriculidae 443 



Limnaeidse 444 



Physidse 449 



Ancylidae 451 



Vitrinidae .'. 452 



Arionidse ? 452 



HelicidsB 453 



Pupidse 455 



Succinidae 457 



Neritidae 457 



Cerithidse , 459 



Melaniidao 459 



Ceriphasiidas 462 



Rissoidae 465 



Viviparidae 466 



Valvatidse 470 



Tabular view of the non-marine fossil mollusca of North America 472 



Spurious and doubtful species 478 



General discussion 479 



407 



