104 



inner, defined from the trochlea by a wide, pitted groove. Its upper pari is 

 destroyed in the specimen. Its. back part barely projects posterior to the 

 position of the trochlea. 



Above the distal articulation, where the bone is expanded to form the outer 

 epicondyle, it is depressed into a broad and unusually deep concave fossa. 



The olecranon fossa is broad and moderately deep, but is not much ex- 

 tended by the protrusion backward of the epicondyles. 



The distal articulation of the humerus presents a well-rounded capitulum 

 on the outer condyle and a broad trochlea extending from it on the inner 

 condyle. The capitulum is convex and narrows behind on a ridge separating 

 the posterior prominence of the outer epicondyle from the trochlea. The 

 trochlear groove is directed obliquely from the fossa in front of the outer epi- 

 condyle downward and inward, then backward, upward, and outward to the 

 olecranon fossa. 



The measurements of the bone are as follows : 



Inches. 



Length of the humerus internally 20£ 



Width transversely of the head 4| 



Width of shaft at the middle from the lower part of the deltoid tract to the pos- 



tero-internal border 4£ 



Thickness of shaft at middle of same position '. 2£ 



Circumference of narrowest part of shaft 9| 



Diameter transversely of narrowest part of shaft •. . . . 2| 



Diameter antero-posteriorly of narrowest part of shaft 3 



Breadth at the epicondyles 7f 



Breadth of distal articulation 5^ 



The mutilated upper extremity of the femur, represented in Fig. 4, Plate 

 XXVI, was found by Dr. Corson, on the buttes west of Dry Creek Cailon, 

 a dozen miles from the former specimens. It is suspected to pertain to Uin- 

 tatherium, though it would appear to have belonged to a larger animal, and 

 perhaps a different species, than the one to which the cranium and humerus 

 are referred. The specimen has about the same size and form as the corre- 

 sponding part in the elephant, but the great trochanter is destroyed. The 

 length of the fragment is a'bout 11 inches. The head is 5 inches in diameter, 

 but its surface is too much mutilated in the specimen to determine whether 

 it possessed a pit for the attachment of a round ligament, or whether it is 

 absent as in recent proboscideans. The outer border of the shaft below the 

 position of the great trochanter is 2| inches thick. From the appearance of 



