616 PROCEEDINGS OF THE ACADEMY OF [DeC. , 



hitherto reported from Japau. It was described from a specimen 

 or specimens in the Leyden ]\Iuseum, collected by Siebokl, and 

 bearing the locality " Japau." It has not been figured, but from 

 the description it differs from T. kiusiuensis in being shorter and 

 wider, with the ribs disappearing on the last whorl. No crest or 

 rib behind the lip is mentioned. 



