PLATE LXIII. 



Zone of Harpoceras serpentinum. 



Fig. 1. Harpoceras elegans, Soioerhy. Side view, natural size. My collec- 

 tion. 



2. — — — Front view of same, do. do. 



3. — - — — Back view do. do. do. 



4. — ovATUM, Young and Bird. Side view do. do. do. 



5. — — — Front view of same, do. do. 



6. — — — Back view do. do. 



7. — — — Lobe-line, mamiified. 



