56 PATAGONIAN EXPEDITIONS I PAL/EONTOLOGY. 



pubis is very slender and is directed more backward and less ventrally 

 than in Dasypns ; posteriorly it becomes quite broad and forms a more 

 elongate symphysis than in the recent genus. The obturator foramen is 

 relatively small and of elongate oval shape, with long axis antero- 

 posterior. 



The femur (Plate XV, fig. 3), which is taken from still another indi- 

 vidual (No. 15,389) is as remarkable as the pelvis; it is rather short, very 

 heavy, antero-posteriorly compressed and with enormous processes for 

 muscular attachment. The head is small, is set upon a short, cylindrical 

 neck and presents upward as much as inward and has also a decided an- 

 terior inclination ; the pit for the round ligament is small, deep, and pos- 

 terior in position ; the great trochanter is immensely developed, rising 

 far above the head ; and is laterally compressed, with its principal diameter 

 in the fore and aft direction ; this same diameter increases toward the 

 proximal end of the process, but the free border is only moderately rugose. 

 A slight depression on the posterior side represents a vestige of the digital 

 fossa, but there is no distinct intertrochanteric line. The second tro- 

 chanter, which also is very large, is much more prominent than in Stego- 

 therium and is separated from the head by a deep notch, which is not 

 present in the latter. The third trochanter arises far down upon the outer 

 side of the shaft and, though rather narrow in the proximo-distal dimen- 

 sion, is of a very unusual prominence and projects outward very abruptly ; 

 the free end is thickened and curved forward, making the anterior surface 

 concave. The distal edge of the process is continued down the shaft as 

 a thin, but very prominent ridge, which reaches its greatest development 

 above the external condyle, recalling the supinatoc ridge of the humerus. 

 From the inner side of the shaft, above the condyle, is given off a small, 

 but prominent and rugose hook. Although it is much compressed antero- 

 posteriorly, the shaft is very broad and heavy ; the posterior surface is 

 nearly plane, while the anterior has a strong median convexity, which 

 runs obliquely from the great trochanter to the inner condyle. The rotular 

 groove is short, but quite broad and concave, with raised inner border. 

 The condyles are very small and widely separated. 



The patella has considerable resemblance to that of Dasypiis, but is 

 relatively less elongate, broader and much thicker ; it also tapers less and 

 the distal end is broader and less pointed. On the posterior side the 

 facet for the femoral trochlea has a prominent median ridge. 



