166 DR. C. W. ANDREWS ON FOSSIL BIRDS [Jail. 19, 



marked towards the lower end, where the bone Avidens out towards 

 the distal articulation. The popliteal fossa is deep, and there are 

 several pneumatic foramina (yjm.f.) opening into it ; it is more 

 strongly defined and extends further up the bone than in JEpyornis. 

 The trochlear surface is rather flattened, and is separated from the 

 intercondylar groove by a well-defined angle. The broad inter- 

 condylar groove is marked with two or three deep pits for the 

 attachment of ligaments. The inner condyle is much as in 

 jE2yyornis, but in the outer the fibular surface is broader and 

 the short ridge forming its supero-internal border is much more 

 prominent. 



Near the middle of the shaft and on its postero- external border 

 there is a small nutritive foramen. 



The Tihio- tarsus (Plate Y. figs. 4 & 5). — The tibio-tarsus is 

 relatively more slender than that of uEpyornis mulleri, and the 

 antero-posterior compression of the shaft is a little less marked. 

 The cnemial crests are well developed and rise high above the 

 articular surface. Immediately beneath the rim of the hinder 

 edge of the proximal articulation there is a deep concavity into 

 which several foramina, probably pneumatic {pn.f.), open. 



The distal portion of the shaft is greatly flattened from before 

 backwards, and its anteiior face is slightly concave fi'om side to 

 side. This concavity is deepest at the groove for the extensor 

 tendons, which runs farther up the bone than in jE2oyorms and is 

 not quite so near the inner margin. The groove is bordered exter- 

 nally by a long and prominent ridge, and on the inner side by a 

 short projection (fig. 5, i), which is evidently the partially ossified 

 base of the otherwise tendinous bridge over the extensor tendons. 

 The distal articulation is almost exactly like that of the tibia of 

 jEpyornis onulleri. The so-called middle trochlea, a slight con- 

 vexity between the outer and inner condyles, is very slightly 

 developed. The post-condylar processes are sharply marked off 

 from the condyles, and the outer at least projects more than in 

 jEpyomis. 



The Fihula (Plate V. fig. 6). — The fibula as far as preserved is 

 160 mm. long. Its upper end is large, and in correlation with 

 the large size of the fibular sm^face of the femur it bears a large 

 articular suii'ace which extends a considerable distance down the 

 outer side of the shaft. The surface for articulation with the 

 fibular prominence of the tibia is oval and deeply concave. About 

 a third of the length of the bone from its distal end there is a 

 prominent tubercle for the insertion of the hiceps cruris. 



The Tarso-metatarsus (Plate V. figs. 7 & 8). — The tarso-meta- 

 tarsus is a compai'atively slender bone, and in general structure 

 corresponds entirely with that of one of the smaller species of 

 jUpyornis, e. g. ^E. hildehrandti as described by Burckhardt. In 

 the proximal articulation the surface for the innei' condyle of the 

 tibia is much the larger, and is much wider antei'o-postei-ioi-ly than 

 that for the outer condyle ; there is no intercondylai- pi'ocess, but, 

 on the other hand, there is a slight median concavity for the 



