262 



University of California. 



[Vol. 3. 



The shaft of the femur is constricted and twisted in the 

 middle, and the expanded ends are turned so as to cut each other 

 at an angle of about seventy-five degrees. The main projection 

 of the twisted proximal end beyond the plane of the distal end 

 seems to be toward the upper side, forming a great trochanteric 

 ridge. The tibial and fibular borders are both markedly concave. 



The tibia and fibula have about half the length of the femur, 

 and both are longer than wide. The tibia differs from the fibula 

 in having the anterior and posterior borders of about the same 

 length. The proximal end is gently rounded, corresponding to 

 the concave articular surface of the femur. The articular facet 

 for the tibiale is long and is normal to the long axis of the bone. 

 The facet for the intermedium is small and oblicpie. The middle 

 or shaft portion is considerably constricted, the indentation of 

 the anterior margin being less than that on the posterior border. 



The fibula is somewhat narrower than the tibia. The straight 

 posterior border is much longer than the deeply emarginate 

 anterior side. The proximal margin is much more oblicpie to 

 the axis than in the case of the tibia. The articular facets for 

 the intermedium and the fibulare are of about equal length and 

 are both oblique. 



In the tarsus the tibiale and distal tarsal one have a quadrate 

 form and are deeply notched in the middle of the anterior border. 

 The pentagonal intermedium, the square distal tarsal two imme- 

 diately below it, and the similarly formed metatarsal two show 

 no emargination. The fibulare possesses a small notch on the 

 outer border. On its distal side there is a large facet for distal 

 tarsal three and a smaller, oblique one on which there probably 

 rested an ossicle belonging to a fourth digit. Similarly there 

 are two facets on the distal end of distal tarsal three, one for 

 metatarsal three and an oblique outer facet of the same size for a 

 metatarsal four. Distal tarsal three has no emargination on the 

 outer or posterior border such as occurs in Leptocheirus on the 

 outer side of the carpals along the borders of the paddles. This 

 is evidently due to the fact that the lateral border was here 

 partially or entirely covered by a series of elements belonging to 

 a rudimentary fourth digit. 



