690 



TITANOTHERES OF ANCIENT WYOMING, DAKOTA, AND NEBRASKA 



Brontotherium Marsh I Brontotherium? sp.. Am. Mus. 1443, manus; Am. Mus. 1047, 



manus and pes (specific reference doubtful). 

 Iq the genus Brontotherium the only postcranial This material may now be described as a whole, the 



elements that are certainly associated with identified several parts being compared with those of Brontops 

 skulls are the following: 1 rohustus (type). 



FiGUEE 623. — Scapulae of Oligooene titanotheres 



Figures prepared by Berber under the direction of Marsh. A, Brontotherium gigas halcheri, Nat. Mus. 4262: A', Outer 

 side; A', inner side; A', distal view. B, BrontopsT: B', Outer side, B', inner side. One-eighth natural size. 



Brontotherium leidyi, Carnegie Mus. 93, skull, lower jaw, atlas, 

 scapula, humerus, radius and ulna, femur, tibia. 



Broniotherium gigas, Am. Mus. 492, sliull, pelvis and sacrum, 

 second dorsal vertebra with ribs, ulna, lunar. 



Brontotherium gigas hatcheri, Nat. Mus. 4262, sliull, lower jaw, 

 the greater part of both fore limbs and feet, parts of both 

 hind limbs and feet, and probably the pelvis. Parts of two 

 other individuals were mixed with this skeleton but have been 

 separated by J. W. Gidley. 



Vertebrae referred to Brontotherium leidyi, Carnegie Museum 



(Figs. 621, 622] 



The atlas of B. leidyi (Carnegie Mus. 93) is com- 

 paratively small, measuring only 305 millimeters in 

 greatest transverse diameter. It differs from that of 

 Brontops rohustus (type) in being proportionately 

 higher, less extended transversely, with less expanded 



