EPOREODON 



93 



The four metacarpals are longer and proportionately slenderer than those of Merycoidodon. 

 The pollex has been lost through evolution. The second and fifth are a little smaller than the third 

 and fourth. The proximal end of the third metacarpal does not overlap the head of the fourth to 

 any extent. The third and fourth metacarpals possess three phalanges and three sesamoids, while 

 the second and fifth have three phalanges and two sesamoids. 



The distal ends of the metacarpals and metatarsals are rounded and prominent, that is, they 

 resemble the carnivores rather than the ungulates. A prominent keel is present on the palmar side 



in u 



Fie. 59. — Eforeodon socialis Marsh. Radius 

 and ulna. CT. Cat. No. 1 3 1 19 Y.P.M. 1/2 nat. 

 size. (After Thorpe, 1931.) 



Fig. 60. — Eforeodon socialis Marsh. Left 

 manus. CT. Cat. No. 13119 Y.P.M. 1/3 nat. 

 size. (After Marsh, 1885.) 



of the extremity. The slender proximal phalanges, with their expanded heads, are also feline in 

 character. The distal articular facets of the median phalanges are carried well back on the dorsal 

 surface, indicating much flexibility of the ungues, which are not so claw-like as in Agriochcerus, 

 although they are not the usual primitive artiodactyle hoof found in Merycoidodon but seem to be 

 intermediate in form. They are laterally compressed and curve downward, terminating in a bluntly 

 rounded point. 



The ilium and parts of the ischium and pubis, together with the complete acetabulum, were 

 found with both specimens (Fig. 61). The ilium is longer than the ischium, and in some respects 

 the pelvis is similar to that of Merycoidodon. The ilium is widely expanded, possessing a stout tuber 

 coxce. The transition from the constricted part in advance of the acetabulum to the expanded portion 

 of the ilium is abrupt, as in Merycoidodon and the recent suillines, whereas in Agriochcerus it is 

 gradual. No trace of the longitudinal ridge, which separates the iliac concavity in the pig, sheep, 

 and deer, is seen in Eforeodon. In this respect it resembles the camel, Agriochcerus, and Mery- 

 coidodon. The acetabulum is deeper than in Sus, and the cotyloid notch is relatively wider. 



The ischium in nearly all respects is closer to that of the pig than of the other artiodactyles. 

 The pubis is short and stout, much like that of Merycoidodon. 



The head of the femur is hemispherical and more exserted from the neck than that of any 

 recent ungulate. The oval depression for the attachment of the ligamentum teres is well defined. 



