On the Teeth of the Megatherium. 61 



The figure, PI. VI. fig. 1. represents the former, and fig. 2. 

 the latter. The tooth of the Megalonix is introduced at fig. 

 3. to exhibit the strong contrast between this animal and the 

 Megatherium. 



The figure of the entire tooth, fig. 1. is nearly square, the 

 angles are rounded, and have a longitudinal groove between 

 them on the external and internal surfaces; this groove is more 

 strongly marked on the latter surface. The teeth are some- 

 what broader from side to side than in the direction of their 

 anterior and posterior surfaces. The posterior or grinding 

 surface will be better understood by a reference to the figure, 

 than by the most elaborate description ; the length of this 

 tooth being five and a half inches, presents a singular and strik- 

 ing coincidence with what is stated above on this point by M. 

 Bru. 



The half tooth, fig. 2. corresponds in every particular with 

 the anterior process of the entire one. The accidental frac- 

 ture enables us to have an excellent view of the arborescent 

 arrangement of the fibres, and exhibits, at the same time, the 

 thickness and structure of the enamel ; this is exhibited in the 

 figure. The colour of the teeth is black ; their cutting sur- 

 faces much worn, indicative of age. 



Although, from the circumstances previously mentioned, it 

 is hardly possible that a complete skeleton will be found, yet 

 enough has been discovered to satisfy us, that the United 

 States, which contains so many relics of huge animals, may 

 add to her " giant brood," the Megatherium. 



