PLATE III. 



Elotherium sp. ; incisor, lateral view. Collection of 1889. Page 28. 



The same tooth, inner aspect. 



Elotherium sp. ; incisor, lateral view. Collection of 1904. 



The same tooth, inner aspect. 



Elotherium, sp. ; incisor, inner view. Collection of 1904. 



Same specimen, viewed from without. 



Ghalicotherium bilobatum, Cope; left lower third premolar, viewed from above. 



Page 54. 

 The same tooth, inner aspect. 

 The same, outer aspect. 

 Mesohippus icestoni, Cope ; right upper second molar, viewed from below ; twice 



the natural size. Page 33. 

 The same tooth, exterior aspect ; twice the natural size. 

 The same, inner aspect; similarly enlarged. 

 The same, anterior aspect ; similarly enlarged. 

 Mesohippus pro?cocidens, Lambe ; left upper molar, as seen from below. Type. 



Page 34.' 

 Fig. 15. Mesohippus propinquus, Lambe ; left upper second molar, viewed from below. 



Type. Page 35. 

 Mesohippus propinquus, Lambe ; right upper second premolar, viewed from below. 

 Mesohippus brachystylus, Osborn ; left upper fourth premolar, as seen from below. 



Page 36. 

 Mesohippus stenolophus, Lambe; right upper third molar, viewed from below. 



Type. Page 36. 

 The same tooth, anterior aspect. 

 The same tooth, outer aspect. 

 Mesohippus planidens, Lambe; left upper first and second molars, seen from below. 



Type. Page 37. 

 Mesohippus assiniboiensis, Lambe ; right upper second premolar, viewed from 



below. Type. Page 37. 

 The same tooth, outer aspect. 

 The same tooth, posterior aspect. 



pa., paracone ; me., metacone ; pr., protocone : hy., hypocone ; pi., protoconule ; 

 ml., metaconule ; ps., parastyle ; ms., mesostyle; mts., metastyle ; d., deuterocone ; te., tetar- 

 tocone ; tr., tritocone. 



Fig. 



1. 



Fig. 



o 



Fig. 



3. 



Fig. 



4. 



Fig. 



5. 



Fig. 



6. 



Fig. 



7. 



Fig. 



8. 



Fig. 



9. 



Fig. 



10. 



Fig. 



11 



Fie. 



12. 



Fig- 



13. 



Fig. 



14. 



Fig. 



16. 



Fig. 



17. 



Fig. 



18. 



Fig. 



19. 



Fig. 



20. 



Fig. 



21. 



Fig. 



22. 



Fig. 



23. 



Fig. 



24. 



