hay: on fossil vertebrates. 51 



PLATE IIL 



Fig. 1. Testudo equicomes. Plan of front of plastron of type. X 1-3. 



Figs. 2-4. Mylodon harlani. Sections of teeth. X 1. 2, Section of first 

 upper tooth. 3, Section of third upper tooth. ^, Section of first lower tooth. 

 In the case of figures 2 and 4 the fronts of the teeth are above. In figs. 

 2 and 4 the inner faces of the teeth are toward the left; in figure 3 it is toward 

 the right. 



Figs. 5, 6. Equun leidyi. Grinding surface of lower premolars and molars, 

 X 1. 5, Left premolars. 6, Right molars. 



