EDENTATA OF THE SANTA CRUZ BEDS. 



173 



surfaces which enter into the elbow joint do not agree very well with such 

 an inference, rather indicating that the hand was already applied to the 

 ground by its ulnar border, at least in an incipient degree. 



(16) The femur is short and heavy and almost always strongly com- 

 pressed and flattened antero-posteriorly, especially in the Planopsidce, but 



t> 



FIG. 25. 



Bones of the hind limb of Santa Cruz Gravigrada, x \. a, Hapalops (femur of H. elongatus, 

 tibia and fibula of H. longiceps) ; b, Analcimorphus leptoceplialus ; c, Prepotherium potens. 



in at least two genera, Schismotherium and Analcimorphus, the shaft is 

 much more rounded and less compressed ; the third trochanter is present 

 in every known specimen, but is much reduced in Prepotherium; the 

 great trochanter is low, but very massive and the digital fossa is ex- 

 tremely small ; the condyles usually resemble those of Megalonyx and the 

 rotular trochlea is broad and shallow. 



