Megatherium of Georgia. 123 



The ribs, also, are too much injured to afford any very dis- 

 tinctive characters. Neither can I observe any thing peculiar 

 in the condyles of the humerus, as we have supposed them to 

 be, for nothing more of this bone remains besides the inferior 

 articulating extremity. The remarkable enlargement de- 

 scribed in the Madrid skeleton is entirely wanting. The two 

 fragments conjectured to be the superior extremities of the ra- 

 dius and ulna, are in the same state, and present nothing but 

 smooth and even concavities, with their edges partly broken. 

 That supposed to be the radius exhibits on one side a smooth 

 facet, where it may have played upon the ulna. One of these 

 pieces is six, the other four inches long ; the diameter of their 

 cavities about four inches. 



Of the two supposed to be carpal bones, the first, which is 

 of a triangular figure, is the smaller. One side is convex and 

 the other concave, with a slight elevation crossing it about 

 the middle, which adapts itself to a corresponding depression 

 in the other bone. It measures nearly five inches in length, 

 and nearly three and a half in breadth, and is about an inch 

 thick. Tiie second is of a singular figure : one side is convex, 

 as in the first ; the other side has one half concave, while the 

 other half swells out into a hemispherical knob. Its outline 

 is quadrangular, and it is a little longer and broader than the 

 first, with its concave end about as thick, and the other nearly 

 three times that thickness, measuring through the knob.. 



The heads of the two femora are both nearly entire, and 

 would perhaps be sufficient of themselves to prove the identi- 

 ty of our animal with the South American species. They are, as 

 observed byM.Bru, "perfectly spherical, and with a superficies 

 very smooth," and measure full twenty-three inches in circum- 

 ference. The dimensions of the skeleton of Madrid are not 

 given in detail in the French abridged description. Even if 

 we had not the evidence afforded by the teeth, these huge 

 condyles would indicate an animal of much superior bulk to 

 the Megalonyx ; for we can hardly imagine that a creature not 



