LOXOLOPHODON AND UINTATHERJUM. 



41 



The Hind-limb. Above the tarsus, the hind-hmb of Uintatherium closely 

 resembles that of Elephas ; the shape of the femur, the angle of the knee, the rela- 

 tions of the tibia and fibula and the two malleoli formed by them offer close 

 points of likeness, (i) The astragalus of Uintatherium, unlike that of Elephas 

 articulates with both the navicular and cuboid bones. (2) The calcaneum of 

 Uintatherium does not articulate with the navicular as in Elephas. (3) The 

 reduction of the lateral toes in Elephas, hallux and minimus, has its parallel merely 

 in the advancing reduction of the hallux in Uintatherium. 



Flower suggests that the reduction of the lateral toes in Elephas is an 

 approach to the odd-toed type of foot. The full-sized minimus and slightly 

 reduced hallux of Uintatherium present us with a simpler type of foot than that 

 of the elephant. 



Points of likeness in the hind-limb of Uintatherium and Rhinocerus are that in 

 both genera (i) the astragalus articulates with navicular and cuboid ; (2) the 

 tibia and fibula are of same relative size and position. The Rhinoceros differs 

 (i) in the possession of a grooved astragalus; (2) in the articulation of the calca- 

 neum with the cuboid ; (3) in the possession of a third trochanter on the femur. 



RESTORATION. 



The restoration of the animal attempted in Plate IV. has been carefully 

 based upon the very considerable portions of the skeletons of Loxolophodon and 

 Uintatherium in the Princeton collection. In outlining the feet the excellent 

 drawings of Prof. Marsh ' have been consulted. Recourse has also been had to 

 the suggestions of Prof. Cope made in 1872,' although the material at his 

 command at that time was quite incomplete. The head is that of L. Speiriaftum, 

 figured also in Plate I., the incisor teeth being added. The remainder of the 

 axial skeleton is represented by the six anterior cervicals of Loxolophodon, and 

 several dorsals of the same, two of which have been placed as sixth and seventh. 

 Of Uintatherium there are a number of dorsal vertebrae, two lumbar, the com- 

 plete sacrum, and the four anterior caudals. Some of these agree so closely 

 with the corresponding vertebrae of the allied genus as to induce the belief 

 that in general outline the spinal columns were closely similar. There was not 

 such a wide difference in the length of the neck as has been asserted. At all 

 events, the Uintatherium vertebrae can be placed and drawn with some assurance, 

 in the Loxolophodon skeleton. The neck was considerably longer than that of the 

 Mastodon ; allowing for the intervertebral discs it is estimated at two feet. The 

 oblique bevelling of the vertebras below indicates that the neck arched upwards 



'Am. Joum. Science and Arts, Vol. XI. p. i68. 

 'Hayden's Survey of the Territories, 3d Series, Vol. XI. 



