TABLE OF CONTENTS. 



Page. 



Introduction 1 



Classification 7 



Synopsis of the genera, subgenera, and sections 8 



References to citations and synonomy of the genera, subgenera, and sections 



of the family Pyramidellidae 17 



West American Pyramidellidse 18 



Genus Pyramidella 18 



Key to the subgenera of Pyramidella 19 



Subgenus Pyramidella 19 



Pyramidella (Pyramidella) bairdi 19 



Subgenus Voluspa 19 



Key to the species of the subgenus Voluspa 20 



Pyramidella ( Voluspa) auricoma 20 



cerrosana 20 



Subgenus Longchaeus 21 



Key to the species of the subgenus Longchseus 21 



Pyramidella (Longchseus) adamsi 21 



bicolor 22 



mexicana 23 



conica 23 



mazatlanica 24 



Species of uncertain standing of the subgenus Longchaeus 24 



Odostomia lamellata .... 24 



subsulcata 25 



vallata 25 



Subgenus Pharcidella 25 



Key to the species of the subgenus Pharcidella 25 



Pyramidella (Pharcidella) hastata 25 



panamensis 26 



moffati 26 



achates 27 



Genus Turbonilla 28 



Key to the subgenera of Turbonilla 28 



Subgenus Turbonilla 29 



Key to the species of the subgenus Turbonilla 29 



Turbonilla (Turbonilla) gilU 29 



delmontensis 30 



centrota 30 



ima 31 



diegensis 31 



acra 32 



lucana 32 



prolongata 33 



Subgenus Chemnitzia 33 



Key to the species of the subgenus Chemnitzia 33 



Turbonilla (Chemnitzia) hypolispa 34 



gabbiana 35 



sepynota 35 



muricata 36 



santarosana 36 



V 



