1917] Stock: Structure of the Pes in Mylodon harlawi 



26! > 



detail the astragalus and navicular of M. harlani from Rock Creek, 

 Texas, and they need not be considered further at this time. In 

 M. robustus the cuboid is apparently longer anteroposterior^ than 

 wide, while in M. harlani the reverse is true, the cuboid being wider 

 transversely than long. The outer (lower) surface of the cuboid 



Fig. 1. Mylodon harlani Owen. Left pes, outer view, X V±- Unguals slightly 

 foreshortened. Bancho La Brea beds. 



Fig. 2. Mylodon robustus Owen. Left pes, X %. After Owen. Pampean 

 Pleistocene beds, South America. 



articulates with a greater portion of metatarsal 5 and with a corre- 

 sponding lesser portion of metatarsal 4 than in M. robustus. In the 

 latter species there is a much smaller articulation of the posterior face 

 with the calcaneum. This difference may also be more apparent than 

 real. 



