I 



I 



1911 YORKSHIRE TYPE AMMONITES XXXIII 



Fig. I 



Fig. 



Fig. 3 



Ammonites quadricornutus, Simpson, 1855 

 Whitby Museum, No. 495, Holotype 

 Fig. I, Side view; Fig. 2, Apertural view; Fig. 3, Peripheral view 



PHRICODOCERAS QUADRICORNUTUM, Simpson sp. 



