148 



TBETIAET YEETEBEATA OF THE EATtM. 



The sustentacular facet (sus.) is separated from the ectal posteriorly by a deep groove 

 which enlarges anteriorly into a deep fossa ; this surface is convex from before back- 

 wards and anteriorly it is continued forwards and outwards as a narrow strip along the 

 top of the anterior edge of the above-mentioned fossa, and in front of this it is continuous 

 with the small surface for the navicular which meets it at about a right angle. The 

 sustentaculum, as a whole, is prominent and sharply defined. The cuboid surface (cub.) 



Text-fig. 51. 



SUS 



Left calcaneum of Palceomastodon beadnelli : A, from above ; B, distal end. 



c^lb., facet for cuboid ; ec, ectal facet ; sus., sustentacular facet; t.c, tuber calcis. 

 The fibular facet lies immediately outside the ectal facet. ^ nat. size. 



is much like that seen in Elephas, but is narrower and does not extend so far towards 

 the inner side of the bone ; it is gently concave. Beneath and to the inner side of it 

 there is a roughened surface which ventrally passes into a prominent tuberosity. The 

 outer face of the calcaneum is concave from above downwards, while the inner side of 

 the tuber calcis is slightly convex, the whole tuber being much more compressed 

 laterally than in Elephas, though perhaps not more so than in Tetrabelodon angustidens. 

 No astragalus large enough to have belonged to P. beadnelli has been found ; but a 



