THE HIND LIMBS. 141 



There is no medullary cavity in the femur, tlie inner texture of the 

 shaft being merely somewhat cancellated, as shown in the woodcuts below. 



PiGUBE 137. — Section of femur oi Binoceras mirabile, Marsh (No. 1200). 

 Figure 138. — Section of same bone (No. 1210). 



Botli figures are one-fourth natiinil size. 



The main dimensions of the femur in one specimen of Dinoceras are 

 given below. 



Measurements of Might Femur. [Dinoceras mirabile. No. 1206.) 



m. 



Length of femur, . ._. - -- .690 



Diameters of head, .12.3-.126 



Distance from summit of head to trochanter minor, ... .. .200 



Height of trochanter minor, — .015 



Transverse diameter through great trochanter, — .215 



Least diameters of shaft, .. .O67-.093 



Transverse diameter of distal end, _ — - .170 



Greatest antero-posterior diameter of distal end, 160 



Least antero-posterior diameter of distal end, . — - .100 



Transverse diameter of inner condyle, ..._ .065 



Transverse diameter of outer condyle, . ._ - .070 



The Tibia. (Plate XLY.) 



The tibia in the Dinoceratu is much shorter than the femur, as in the 

 elephant and the mastodon, and considerably resembles the same bone in 

 these animals. It differs noticeably in the greater prominence of the 

 tuberosity for the attachment of the patellar ligament. 



The proximal articular surfaces for the condyles of the femur are 

 confluent, or very nearly so, being sejiarated b}' only a low, smooth and 

 rounded ridge,- as seen in Plate XLV, figure 3 a. The inner face is 

 larger in antero-posterior diameter than the outer, and is concave 



