S2 ROYAL SOCIETY OF CANADA 



Plate II. 



Figure 1. — Inferior view of crown of upper molar of Mesohippus 



westoni; twice the natural size. ^ 



Figure la. — Exterior aspect of the same; twice the natural size. 

 Figure lb. — The same viewed from within; twice the natural size. 

 Figure Ic. — Anterior view of the same; similarly enlarged. 

 Figure 2. — Inferior view of crown of upper molar of Mesohippus 



prœcocidens; natural size. 

 Figure 3. — Mesohippus propinquus. View of crown of upper molar 



from below; of the natural size. 

 Figure 4. — Mesohippus propinquus. A similar view of an upper pre-, 



molar; natural size. 

 Figure 5. — Crown of upper premolar of Mesohippus hrachystylus, 



viewed from below; natural size. 

 Figure 6. — Inferior view of crown of upper molar of Meeohippus 



stenolophu^; natural size. 

 Figure 6a. — The same tooth viewed from without; natural size. 

 Figure 6b. — Anterior aspect of the same tooth; natural size. 

 Figure 7. — Mesohippus planidens. Cro-wms of two upper molars viewed 



from below; natural size. 

 Figure 8. — Mesohippus assinihoiensis. Crown of upper premolar as 



seen from below; natural size. 

 Figure 8a. — Exterior aspect of the same; natural size. 

 Figure 8b. — Posterior view of the same; natural size. 



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

 protoconule; ml., metaconule; ps.. parastj^le; ms., mesostyle; mts., meta- 

 style; d., deuterocone; te., tetartocone; tr., tritocone. 



