PLATE VI. 



Fig. Page. 



1. Ciydoniceras discus (Sow.). — Sudbrook. In the Sedgwick Museum. 



Showing sutures. 54 



2. Ciydoniceras hochstetteri (Oppel). — Norton Brize. In the Museum of 



Practical Geology (no. 8647). Showing sutures. 55 



3. Ciydoniceras piychophorum (Neumayr). — Trowbridge. In the British 



Museum (no. 33541). 3 a, side view ; 3 b, sectional view. 50 



4. Ciydoniceras legayi (Rigaux and Sauvage). — Sudbrook. In the Sedgwick 



Museum. Showing sutures. 57 



5. Ciydoniceras legayi (R. and S.). — Sudbrook. In the Sedgwick Museum. 



Peripheral view. 57 



6. Ciydoniceras legayi (R. and S.). — Rushden. In the Collection of Mr. 



W. H. Hudleston, Showing the body chamber and last suture. h7 



