186 TEETIAEY VERTEBRATA OF THE FATtTM. 



flattened ischial tuberosity {isc.t.). The outer surface of the ischium is in almost the 

 same plane as the gluteal surface of the ilium. The pubis (pu.) is a stout bar of bone 

 compressed from above downwards^ On its anterior border beneath the acetabulum is a 

 well-marked pectineal tuberosity (pt.); towards its inner end it widens out and terminates 

 in a flat oval surface by which it unites in symphysis {sym.) with its fellow. Behind 

 this surface there runs back to the ischium a thin bar of' bone, closing the obturator 

 foramen. This bar has a thin sharp edge, and neither it nor the ischium seems to have 

 united with the corresponding portion of the opposite os innominatum. The obturator 

 foramen {obt.f.) is an elongated oval. The acetabular cup (acet.) is nearly circular in 

 outline ; it is deep, its edges being prominent and thickened, particularly in front. 

 Its border is complete, there being no cotylar notch, which is only represented by a 

 passage (/.) running through the posterior wall of the acetabulum from just above the 

 anterior end of the obturator foramen and opening into the posterior end of the pit for 

 the ligamentum teres (J.t.), which is a deep elongated depression at the bottom of the 

 acetabulum. This arrangement is also found in a very similar pelvis of Bracliyodun 

 africanus from Moghara and in Hippopotamus : this last genus, in fact, seems to be 

 intimately related with these African Anthracotheres, and annectant forms similar 

 to Merycopotamus will probably be discovered in the Miocene beds between Moghara 

 and the Wadi Natrun, in the Lower Pliocene deposits of which remains of a primitive 

 Hippopotamus have already been found. The dimensions (in centimetres) of this 

 specimen are : — 



Total length of os innominatum . 37'2 



„ ilium from centre of acetabulum . . . . 20'4 



„ ischium from centre of acetabulum . . 17'5 



Width of peduncle of ilium 6 



„ crista ilii 16-4 



Diameter of acetabulum 5-2 



Length of obturator foramen 9 '4 



Width of pubic bar on inner side of obturator foramen . . . 1"5 



Length of symphysial surface of pubis . 5-5 



Depth of symphysial surface of pubis 3 



Iff. 9242. Plaster cast of the above specimen. Made in the British Museum. 



C. 9224. Portion of left os innominatum, wanting part of front of ilium and the pubis. 



M. 8866. Portion of left os innominatum. Presented by the Egyptian Government, 1904. 



M. 8864a. Complete left tibia. The most notable character of this bone is the slenderness of its 

 distal portion compared with the heaviness of its upper end. The outer facet for the 

 femur is concave from side to side and strongly convex from before backwards ; its 

 inner edge forms a rounded ridge separated by a groove from the raised outer edge of 

 the inner facet, the two together forming a bifid intercondylar prominence. The inner 

 facet is concave from side to side and nearly flat from before backwards. In front of the 

 articular surface the upper end of the large cnemial crest forms a broad flattened surface. 

 The upper portion of the shaft is trihedral ; its antero-external side is deeply concave, 

 the posterior slightly so ; this latter face is overhung by the posterior border of the 

 proximal articulation. The cnemial crest disappears about halfway down the shaft. 



