PLATE 19. 



LOWER TEETH OF MERYCHIPPUS FROM NORTHEASTERN COLORADO. 



COMPARISON OF THE TEETH AT DIFFERENT STAGES OF WEAR IN TWO SPECIES FROM THE MIDDLE MIOCENE OF COLORADO. 

 THE UPPER TEETH OF THE SAME INDIVIDUALS ARE FIGURED ON PLATES 15, 16. 



All figures natural size. 



1. Mcrychippus sejmictus Cope, referred specimen, Am. Mus. 8273. Teeth 

 little worn. 



2. M. sejunctus Cope, type, Am. Mus. 8291. Teeth well worn. 



3. M . campestris Gidley, type, Am. Mus. 9096. Teeth little worn. 

 (Drawn from left lower series reversed, the right ramus being diseased.) 



4. M. campestris Gidley, referred specimen, Am. Mus. 9459. Teeth much 

 worn. 



Pawnee Creek, Col. Middle Miocene 



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