Fossil Bones from Oregon Territory. 



139 



and a quarter inches ; across the articulating surface, six inches j 

 its length (from D to H) is six inches. 



Fig. 3. Fig. 4. 



The structure of the upper and lower articulating surfaces, the 

 great size and outward situation of the great tuberosity, the prom- 

 inence on the outer part of the bone, together with the marked 

 resemblance, so far at least as the adaptation of means to ends 

 goes, between this bone and that of the ant-eater, led me to ima- 

 gine that it was probably the humerus of a large animal which 

 had the power of abducting the bone somewhat, of freely rota- 

 ting the fore-arm, and who obtained his food by digging. Whe- 

 ther it belonged to the same animal with the tooth above de- 

 scribed, which I suspect may have been the case, I have not the 

 means of determining with certainty. There are apparent and 

 essential differences between Cuvier's plate of the humerus of 

 the Megatherium and the specimen under examination, although 

 there appears to be some considerable resemblance. It still less 

 resembles that of the fossil elephant, or any other I can find fig- 

 ured. My means of reference however are so scanty, that it 

 would be folly for a tyro in palaeontology to attempt to name it, 

 and I must leave it for you and others better qualified to say to 

 what genus it belongs, if not to some one of the megatherioid 

 tribe. 



