Megatherium of Georgia. 121 



The fragments of teeth in Dr. Habersham's collection, for 

 there is not one entire, agree with Bru's description of those 

 in the skeleton of Madrid, so far, at least, as it is given in the 

 French abridgment. There are the sockets of four in the 

 right lower side, and consequently eight teeth in all, in the 

 lower jaw, the six posterior being the greatest. They are 

 square with rounded angles, and a groove between on the in- 

 ner and outer sides, and are longitudinally striated. The infe- 

 rior pyramidal cavity may be observed with advantage in the 

 right second molar, which remains in the socket : but the ter- 

 minating points are broken off from this as well as from all 

 the others. Consequently, we are not enabled to ascertain 

 their precise length, but it appears to have been at least seven 

 inches, and probably more. 



The heaviest of our teeth, which is the first of the right 

 side, weighs nine and a quarter ounces. The fourth of the 

 left side weighs nine ounces. To make them agree with the 

 weights of the corresponding teeth as stated by B u, we must 

 suppose that more than half has been broken off the former, 

 and from the latter nearly two thirds. This, from a compari- 

 son with the sockets, I should hardly suppose to be the case, at 

 least with the latter. 



The peculiar form of the crown of these teeth is not well 

 represented in any figure I have seen, excepting that given by 

 Professor Mitchill, to which the reader is referred. Their 

 posterior crest is higher than the anterior. The posterior 

 crest is known by the curvature of the tooth corresponding 

 with that of the socket. This peculiarity does not appear in 

 the figure in the " Ossemens Fossiles," but rather the contrary. 



Their remarkable structure, so much unlike any before ob- 

 served, is still more deserving of a particular description. The 

 tooth is covered externally with a coating of enamel, extreme- 

 ly thin, and uniformly so on all sides, and which does not 

 extend over any part of the crown. Within is a coating of 

 bone or ivory, which at the sides of the tooth is as thin as the 



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