PLATE III. 



Fig. 1. Elotherium sp. ; incisor, lateral view. Collection of 1889. Page 28. 



Fig. 2. The same tooth, inner aspect. 



Fig. 3. Elotherium sp. ; incisor, lateral view. Collection of 1904. 



Fig. 4, The same tooth, inner aspect. 



Fig. 5. Elotherium sp. ; incisor, inner view. Collection of 1904. 



Fig. 6. Same specimen, viewed from without. 



Fig. 7. Chalicotherium bilobatum, Cope; left lower third premolar, viewed from above. 



Page 54. 

 Fig. 8. The same tooth, inner aspect. 

 Fig. 9. The same, outer aspect. 

 Fig. 10. Mesohippus westoni. Cope ; right upper second molar, viewed from below ; twice 



the natural size. Page 33. 

 Fig. 11. The same tooth, exterior aspect ; twice the natural size. 

 Fig. 12. The same, inner aspect; similarly enlarged. 

 Fig- 13. The same, anterior aspect ; similarly enlarged. 

 Fig. 14. Mesohippus prcecocidens, 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. 

 Fig. 16. Mesohippus propinquus, Lambe; right upper second premolar, viewed from below. 

 Fig. 17. Mesohippus brachystylus, Osborn; left upper fourth premolar, as seen from below. 



Page 86. 

 Fig. 18. Mesohippus stenolophus, Lambe ; right upper third molar, viewed from below. 



Type. Page 36. 

 Fig. 19. The same tooth, anterior aspect. 

 Fig. 20. The same tooth, OTiter aspect. 

 Fig. 21. Mesohippus planidens, Lambe ; left upper first and second molars, seen from below. 



Type. Page 37. 

 Fig. 22. Mesohippus assiniboiensis, Lambe; right upper second premolar, viewed from 



below. Type. Page 37. 

 Fig. 23. The same tooth, outer aspect. 

 Fig. 24. The same tooth, posterior aspect. 



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

 mi., metaconule ; ps., parastyle ; ms., mesostyle; mfs., metastyle ; d., deuterocone ; <e., tetar- 

 tocone ; ir., tritocone. 



