XII TABLE OF CONTENTS. 



Page. 



Subgenus Amaura 218 



Key to the species of the subgenus Amaura 218 



Odostomia (Amaura) lastra 219 



kennerleyi 219 



elsa 220 



beringi 220 



satura 221 



farallonensis 221 



sillana _ _ 222 



talpa 222 



krausei 223 



orcia 223 



gouldi 224 



arctica 224 



avellana 225 



moratora 225 



pesa 226 



nota 226 



iliuUukensis 227 



nuciformis 227 



canfieldi 228 



aubturrita 228 



martensi 229 



Subgenus Scalenostoma 229 



Key to the species of tlie subgenus Scalenostoma 230 



Odostomia (Scalenostoma) dotella 230 



rangii 230 



Subgenus Heida. 231 



Odostomia (Heida) panamensis 231 



Subgenus Odostomia 231 



Key to the species of the suligenus Odostomia 232 



Odostomia (Odostomia) farella 232 



dinella 232 



coronadoensis 233 



mammillata 233 



Explanation of plates 235 



Index 249 



