Plate XXXV 



Evolution of the Upper Molars in the Notharctina? 

 All figures three times natural size. 



For the generic and specific characters see especially Matthew, 1915, Bull. Amer. Mus. Nat. Hist., XXXIV, pp. 434-444, and Grangei 

 and Gregory, 1917, idem, XXXVII, pp. 845-856. The morphological and phylogenetic aspects of this series are discussed in the present 

 work, pages 133 to 143. 



