46 BULLETIN 111, UNITED STATES NATIONAL MUSEUM. 



The followinof are the museum records: 



DENTAHUM (ANTALIS) PSEUDOHEXAGONUM Ihering. 



Plate 6, figs. 1, 2, 3. 

 Dentalium pseudohexagonum Ihering. (Reference not available.) 

 This is a species, the shell of which is characterized by nine primary, 

 well-elevated narrow rounded ribs, not at once increased by second- 

 aries on the tip, and which are separated by wider flat spaces be- 

 tween them. The intercostal spaces are crossed by coarse, rather 

 widely spaced growth lines, which in the posterior portion of the shell 

 become more prominent. The intercalation of one rounded secondary 



