1918 



YORKSHIRE TYPE AMMONITES— II CXIVa 



Fig. i 



Fig. 2d 



Fig. 2b 



Fig. 2a 



Fig. 2C 



Ammonites bifrons, Bruguiere, 1789 



Fig. 1, Copy of Protograph, Lister, 1678, PI. vi, f. 2 ; Figs. 2a-d, Topotvpe 



(Holotypc ?), Coll. V. E. Robson, F.G.S. 



HILDOCERAS BIFRONS, Bruguiere sp. 



