THE PALEONTOLOGY OF THE ZORRITOS FORMATION 

 OF THE NORTH PERUVLAN OIL FIELDS 



By Edmund M. Spieker 



CONTENTS 



Page 



Introduction i 



Previous work i 



Geologj- of the Zorritos District 3 



Analysis of the fauna 12 



Systematic Part — 



Family Terebridae 35 



, Conidae ^7 



Cancellariidae 42 



Marginellidae 43 



Buccinidae 45 



Nassidae 48 



Muricidae 51 



Doliidae 52 



Cypraeidae 55 



Cerithiidae 56 



Turritellidae 59 



Naticidae 87 



Turbinidae 91 



Nuculidae 93 



Arcidae 95 



Pectenidae 125 



Anomiidae 127 



Crassitellitidae 128 



Lucinidae 132 



Cariidae 134 



Veneridae 138 



Tellinidae 156 



Psammobiidae 162 



