Platyostoma lineata, var. callosa. 

 Fig. 14. Lateral view of a specimen. Page 184 



Gomphoceras turbiniforme. 



Fig. 15, 16. View of two specimens showing variation in size. Page 194 



Gomphoceras oviforme. 



Fig. 17. Side view of a specimen. Page 193 



Fig. 18. View of the aperture of a specimen. 



