PLATE LXXXII. 



Zone of Lytoceras Jurertse. 



Fig. 1. Harpoceras Aalense, Zieten. Side view, natural size. Lyt. Jurense Bed, 



Wasserelflngen, Germany. My collection. 



2. — — — Front view, do. do. do. 



3. — — — Side of another specimen do. do. 



4. — — — Siphonal area, do. do. do. 



5. — costula, — Side view, natural size. Variety with coarse 



ribs, from my collection. Wasserelflngen. 



6. — — — Variety with fine ribs, from my collection. 



Frocester Hill. 



7. — acutum, Tate. Side view, magnified two diameters. Chipping 



Warden, Northamptonshire. My collection. 



8. — — — Front view, do. do. 



9. — bicarinatum, Munster. Side view, natural size. Coaley. Col- 



lection of Museum, School of Mines. 



10. — — — Front view, do. do. 

 10 a. — — — Suture line, magnified. 



11. — — — Front view of a specimen eopied from 



d'Orbigny, ' Pal. Franc. Jurass.,' 

 pi. 114, fig. 3. 



12. — discoides, Zieten. Side view, natural size. Coaley. My col- 



lection. 

 12 a. — — — Suture line, highly magnified. 



13. — — — Front view, natural size. My collection. 



14. Amaltheus lenticularis, Young. Side view, natural size. Whitby. Col- 



lection of Museum, Royal School of 

 Mines. 



15. — — — Front view, do. do. 



