0. a Marsh— Principal Characters of the Dinocerata. 167 



those of Proboscidians. The atlas and axis are very similar to 

 those of the elephant, but the rest of the cervicals are propor- 

 tionally longer. The dorsal and lumbar vertebrge have the artic- 

 ular faces nearly flat, and the lumbars have an inferior ridge on 

 the median line. There are four sacral vertebrae, the last being 

 }d, trans- 

 The 



segments of the sternum were well ossified, and most of them 

 were flattened vertically. 



The scapula, in its general form, is similar to that of the 

 elephant, but there is much less constriction above the glenoid 

 fossa. The latter is elongate, deeply concave longitudinally, 

 and nearly flat transversely. The spine extends downward 

 nearly to the glenoid border. The coracoid portion is a rugose 

 protuberance, separate from the margin of the articular fossa. 

 The humerus is short and massive, and in its main features 

 resembles that of the elephant. One of the most marked dif- 

 ferences is seen in the great tuberosity, which does not rise 

 above the head, and is but little compressed. The condylar 

 ridge, moreover, of the distal end is tubercular, and not con- 

 tinued upward on the shaft. The lower extremity of the hu- 

 merus is much like that of the rhinoceros, and the proportions 

 of the two bones are essentially the same. The radius and 

 ulna are nearly of the same size. The head of the radius rests 

 on the middle of the ulnar articulation, and hence the shaft of 

 this bone does not cross that of the ulna so obliquely as in the 

 elephant. The ulna has a small face for articulation with the 

 lunar, as in the elephant 



There are five well developed toes in the manus, which is 

 well shown in Plate VI, figure 2. The carpal bones are eight 

 in number, and form interlocking series, as in Perissodactyls. 

 The scaphoid resembles that bone in the elephant, but is shorter 

 and stouter. Its proximal end is rounded, forming about one- 

 fourth of a sphere. On its distal end, the articular faces are 

 confluent. It supports the trapezium and trapezoid. The pyra- 

 midal sends down an outer angle to articulate with the fifth 

 metacarpal, as in Elephas. The trapezoid is the smallest bone 

 in the carpus. The magnum is supported by the lunar, and 

 not at all by the scaphoid. The unciform is the largest 

 carpal bone. It has the usual metacarpal faces well marked, 

 and separated by ridges. The metacarpals are of moderate 

 length, and the third is about equally supported by the magnum 

 and unciform. The articulations for the phalanges are nearly 

 flat, indicating but little motion. The phalanges are very short, 

 and the distal ones rugose. 



. The pelvis is much expanded, as in Proboscidians. The 

 ilium is suboval in outline. The pubis is slender and short, 



