108 ON THE EXTINCT MAMMALIA OF 



terior articular face. Another series of three lumbar vertebrae, partially imbedded in 

 the rock and of the same length as the preceding, retain portions of the spinous pro- 

 cesses, measuring an inch in width. A last lumbar vertebra attached, with a portion 

 of the sacrum, to a fragment of rock, has the body a little over an inch in length and 

 ten lines in width transversely at its posterior articular surface. Its costal processes 

 are transverse, of robust proportions, an inch in length and half an inch in width. 



The portion of sacrum above mentioned measures nearly three inches in width 

 at the tips of the aloe, and its articular surface for the lumbar vertebra is ten lines 

 wide. 



Anterior extremities. — Fragments of several scapulae of Oreodon Oulhertsoni indicate 

 a bone nearly like that of recent ruminants, but with the dorsum more equally 

 divided by the spine. The glenoid articulation, in a specimen, from the summit of 

 the coronoid process measures fourteen lines, and transversely nine and a half lines. 



Fragments of humeri of 0. Culhertsoni are numerous, and similar ones of 0. 

 gracilis are not unfrequent. The form of the bone and its proportions are nearly as 

 in the Peccary. In the former species its estimated length is about six inches ; a 

 specimen of the latter species measures a little over four inches. The longer diameter 

 of the head is transverse, and terminated by the lesser tuberosity. The distal articu- 

 lation presents a construction like that of recent ruminant and suilline animals. 



Various specimens of the humerus of 0. Culhertsoni and 0. gracilis exhibit the 

 following extremes of measurement : 



Circumference at the middle of the shaft in 0. Culhertsoni, 



" " " 0. gracilis, . 



Diameter of head with greater tuberosity in 0. Culhertsoni, 



" " ■ " 0. gracilis, . 



Transverse diameter of distal articulation in 0. Culhertsoni, 



" " " 0. gracilis, . 



Fragments of the bones of the fore-arm of Oreodon are comparatively few. Several 

 specimens, consisting of portions of both bones held in juxtaposition by matrix, indi- 

 cate the radius and ulna to be distinct, and relatively to each other as well developed 

 as in the Hog, but proportionately more slender or longer in relation with the 

 thickness. 



Measurements derived from several specimens of the fore-arm bones of 0. Culhert- 

 soni and 0. gracilis are as follows : 



Largest. 



Smallest. 



Lines. 



Lines. 



. 22 



18 



. 14 



11 



. 21 



15 



. 12 



8 



. 10 





. 7 





