PLATE XII. 



PAGE 



Fig. 11. Septum of Ammonites Traskii. 63 



Pig. 12 b. Septum of A. ramosus. 65 



The dorsal lobe was obliterated by weathering. 



Fig. 13 />. Septum of A. Hoffmannii. 65 



Fig. 14. A. Remondii. 66 



Coarsely costate variety. 



Fig. 15. A. Remondii. 66 



Nodose variety. 



