Page. 

 Fig. 13. Planokhis sPEcrAUiu.s 18!) 



13. A small specimen (undtT side view). 

 ISffl. A profile view of same. 



13 b. An upper view of same 



13 c. A profile view of a larger speeimun. 



13 rf. Au upper view of a large distorted specimen. 



13 e. View of under side of same. 



13/. Au under view of a smaller specimen. 



Fig. 14. Planorbis spkctabilis, var. Utahensis 190 



14. Upper side, natural size. 



14 a. Under side, same. 



14 b. Upper side view of another specimen. 



14 c. Profile view of same specimen represented by fig. 14. 



Fig. 15. Campeloma (undt. sp.) 181 



15. A large, imperfect specimen, somewhat distorted (widened) by compression (lines 



of growth too strong and too straight), so as to appear rather wider than natural. 

 15 o. An opposite view of same specimen. 



Fig. 10. Probably the young of the above species 



16a. Another view of another specimen. 



16 6. Another specimen, with the spire broken away. 



Fig. 17. Campeloma macrospira? f young specimen) , 179 



17. A dorsal view. 



17 a. Au opposite view of same. 



Fig. 18. Viviparus CoxRADi? 178 



18. An imperfect specimen from Bear River, Utah. 



18 a. A specimen from the original locality on the Upper Missouri, figured here for com- 



parison. 



Fig. 19. PYIiGUI.irERA HUMEROSA 176 



19. A large specimen, with the lip broken, so as to give an unnatural angularity to the 



basal outline. 

 19a. Another specimen, with the apex of the spire broken ofi', but showing the form of 

 the aperture. 



