18 AMERICAN JOURNAL 



L. erecta (Natica), Whitfield. — Ib. ; fig. 11. 



Deshayes figures a number of species of this Eocene genus 

 under the generic name of Lacuna. I believe the genus in- 

 habited deep water, unlike Lacuna, and probably terminated 

 its existence at the close of the Eocene period. Certainly it 

 is as yet unknown in a later formation. 



CYCLOMERA, Conrad. 



I propose this name, in place of Cycloceras, given by me as 

 a subgenus of Baculites, which name is pre-occupied. 



