THE PEJEVAL8KY HOESE. 55 



ischii is not so thick. In the following table the size of the pelvic 

 bones of E. jJrjevalskii and the Tarpan are given: — 



Width of the pelvis between the two external anterior 1 



angles of the ilia J 



Distance from the inner anterior angle of the ilium to the 1 



pubis ... ... ... ... ... ... ... j 



Distance between the inner anterior angles of the two ilia ... 

 Least width of the ilium on a level with the incisura 1 



ischiadica ... ... ... ... ... ... j 



Height of the pelvis from a horizontal surface to the tip of l ,^.0 ^.n 



the inner anterior angle of the ilium ... ... J 



Width of the ilium from the inner anterior angle to the 



outer anterior angle 



Width of the oliturator foramen 64 70 



Length of the obturator foramen ... ... ... ... 42 45 



260 238 



THE FEMUR (Fig. 23), like the humerus, is thicker than the 

 corresponding bone of the Tarpan. It is especially strong in its 

 distal part. Its length is less, and its width at the distal end is 

 about 4 cm. greater than in the femur of the Tarpan ; although the 

 proximal end is narrower than in this animal. So far as the shape 

 of the femur of the Prjevalsky horse is concerned, it presents 

 nothing striking; except the somewhat strong development of the 

 liead (caput femoris) and the relatively large size of the trochanter 

 medius : — 



E. prjevalskii. Tarpan. 



mm. mm. 



Greatest length of the femur 373 378 



Length from the caput femoris ... ... ... ... 337 348 



Width on a level with the caput femoris ... ... 109 111 



Width at the distal articular surface 81 81 



Width at the eondylus internus 118 114 



THE TIBIA. — Of the bones of the leg, the tibia alone is avail- 

 able ; the fibula is missing. A comparison of the tibia of E. 

 2Jr jevalskii with the same bone of the Tarpan leads to the same 

 results as in the bones already described. In the Prjevalsky horse 

 the bone is wider and more massive, as well as shorter ; and all its 

 elevations and depressions are more pronounced. The differences 

 between the tibia of E. prjevalskii and of the Tarpan are here 

 shown : — 



Length of tibia on the anterior side 

 Greatest length ... 

 Length on the outer side... 

 Width of the proximal end 

 Width of the distal end ... 

 Width of the distal articular surface 



