EEEMOPEZUS EOCiENUS, 



259 



approximation to this condition is seen in StrutUo, and still more in BJiea. The 

 surface between the postcondylar processes is slightly concave, and above passes into 

 the posterior surface of the shaft, which, like the articular end, is strongly compressed 

 from before backwards. The lateral faces of the condyles bear deep pits for the 

 attachment of ligaments (text-fig. 84 B). 



The posterior face of the shaft passes by a gentle slope into the sharp antero-internal 

 border of the bone, which is continuous with the upper angle of the inner condyle, as 

 in Casuarius and Dromceus. The anterior face of the shaft near its inner border is 

 deeply channelled by the groove for the extensor tendons (text-fig. 84 A, e.g.) ; this 

 groove is closed at its lower end by a strong ridge running upwards and outwards 

 towards the lower border and forming a prominent rugose surface above the outer 



Distal end of left tibio-tarsus of Eremopezus eocmnus (type specimen) : A, from front ; B, from outer side ■ 



C, from behind. (From Proc. Zool. Soc.) 



a., angle between outer condyle and postcondylar surface ; e.g., extensor groove ; i.e., inner condyle ; 

 o.c, outer condyle ; t., tubercle marking base of tendinous bridge, f nat. size. 



condyle. There is no extensor bridge, but a slight ridge along the inner side of the 

 groove marks the insertion of a strong tendinous sling (t.). 



Compared with the tibio-tarsi of other Eatites this specimen appears to combine the 

 characters of several of them. In the depth of the extensor groove it approximates to 

 Bhea and yEpyornis. The oblique ridge which blocks the lower end of the groove 

 occurs also in Struthio, though in this case the groove itself is much narrower. 

 In JEpyornis, on the other hand, the ridge is wanting, and the groove runs nearly 

 down to the condyles. The form of the outer condyle and its relations to the 

 postcondylar process are similar to what is seen in Bhea, and to some extent also 

 in Struthio. 



There seems to be no doubt that this fragment indicates the existence of a large 

 Eatite bird in the Upper Eocene beds of Egypt, but much more material is necessary 

 before its relationships can be determined satisfactorily. 



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