Fig. 94. Humerus,
anterior side—
⅕ natural size.
Fig. 95. Ulna anterior
side—⅕ natural size,
after Gaudry.
The lower half of the humerus is present, and characterized by very wide epicondyles, a shallow supratrochlear fossa, a moderately deep anconeal fossa, no foramen, and a wide shallow trochlea. The ulna, according to Gaudry, is a long, heavy, nearly straight bone, with a shallow sigmoid notch, and with a large olecranon process which is not bent backward to any marked degree. The proximal end of the radius has a broad doubly curved articular surface to fit the full width of the humeral trochlea. Its ulna facet is a short broad area just below the margin of the bone, and would indicate little or no rotary motion of the fore arm. Most of the shaft is lacking but what is present indicates a very slender bone.
Fig. 96. Upper end of radius,
ulnar side—
⅕ natural size.
Fig. 97. Left tibia,
posterior side—
⅕ natural size.
Fig. 98. Astragulus,
dorsal aspect—
½ natural size,
after Ameghino.