Fauna and Stratigraphy of the Stormberg Series. 



431 



and there is a well-marked broad depression between them on the 

 anterior face. The posterior surface of the distal end is almost flat, 

 the lateral condyle being somewhat thickened. 



The bone is 500 mm. long. The distance from the lower end of 

 the lateral process to the distal end of the bone is 260 mm. The 

 shaft is 55 mm. thick and 67 mm. broad. The distal end is 155 mm. 

 broad, the thickness at the lateral condyle is 65 mm., and at the 

 medial condyle 63 mm. 



Radius. The left radius presents no features of unusual interest. 

 It is slightly shorter than the ulna, having a length of 280 mm. 

 The proximal and distal ends are each 89 mm. wide, while the shaft 

 at its narrowest is 43 mm. wide. 



There is also preserved a right radius, somewhat smaller than the 



Fig. 43. Mdanorosaurus readi, Htn. 

 Right_ulna of type. X J. 



corresponding bone of the other side. It is 250 mm. long. The 

 proximal end is flattened, while the distal end is thicker and stronger. 

 In both bones the proximal articular sin-face is concave in front and 

 convex behind as in Plateosaurus and other forms. 



Ulna. The right ulna is complete, being 300 mm. long. The 

 proximal end is expanded and has a triangular articular surface, of 

 which the anterior and posterior angles are sharper than the lateral 

 angle. The anterior point is directed forwards, the posterior one 

 backwards and outwards. The posterior half of the surface is strongly 

 convex in its middle portion, being raised considerably above the 



