PARASTRAPOTHERH'M 147 



a heavy club-like distal end. The ulna has a short but 

 heavy olecranon process, with a prominent coronoid 

 process. The sigmoid notch is shallow, but the articular 

 surface expands on both sides, so that it covers the full 

 width of the humeral trochlea on the posterior side. Dis- 

 tally the ulna is not so heavy as the radius. 



Under the name Pyrothcrium romeri, Ameghino* figures 

 a carpus and metacarpus, which Tournierf however assigns 

 to Parastra pother ium, probably P. herculeum; and figures 

 a carpus and metacarpus of the same type, but smaller, 

 which he attributes to Parastra pother ium. I, however, 

 can not see how such a small foot can belong to so large 

 an animal, and feel that, until evidence of direct association 

 is given, it is best not to consider these feet as belonging 

 to Parastra pother ium, but rather to Pyrothcrium. 



Of the femur I have only the distal end, which, however, 

 corresponds completely with the one figured by Gaudry. 

 It is a long bone, slightly shorter than the humerus, with 

 a small head, set on a short and poorly outlined neck. 

 The greater trochanter is wide and rugose, rising to about 

 the same height as the head. The lesser trochanter is 

 not distinguishable. About the middle of the shaft there 

 is a powerful third trochanter, which continues as a narrow 

 ridge upward to the greater trochanter, and downward 

 in a similar narrow ridge almost to the outer condyle. 

 At the proximal end the shaft is greatly flattened, but in 

 the central and lower parts becomes almost circular in 

 section. The two condyles are set wide apart, project 

 considerably behind the posterior face of the shaft, and 

 and are only slightly convex. The trochlea is of moderate 

 width, short, and shallow. 



Gaudry outlines a short, heavy, rugose calcaneum which 

 has but a short tuber; a flat navicular; a small cuboid; 

 and an astragulus with only a slight convexity of the 



* Bol. Inst. Geog. Argcn., t. 18, p. 442, fig. 25, 1897. 

 t Bui. Soc. Geol. France, ser. 4, t. 5, p. 305, 1905. 



