76 



border. The postscapular fossa is larger and less concave ; 

 both fossae, as they approach the upper border, gain greatly 

 in thickness. 



The spine rises from the supra-scapular border, and ex- 

 tends to within an inch from the glenoid cavity. It is decid- 

 edly antroverted ; thickest and highest near glenoid cavity ; 

 thinnest and lowest in the middle, expanding again at its 

 upper extremity ; its acromio-scapular notch is long and 

 shallow. 'The acromion is rudimentar3\ 



The coracoid process is a low, rugose tuberosity ; the 

 coraco-scapular notch is short and low. 



The internal surface of the scapula has a large, smooth 

 median ridge, extending the whole length of the bone, sepa- 

 rating it into slightly concave fossae. About two thirds up, 

 the median ridge sends obliquely up two branches, forming a 

 V, superimposed upon the main ridge ; but these disappear 

 before they reach the upper extremity. The whole inner 

 surface is curved outward, presenting a concave appearance 

 throughout. 



The glenoid cavity is deep, f)void in form, with its great- 

 est diameter fore and aft, and its smaller end behind. 



The resemblance between the scapula of Uintatheriuni 

 and that of the Proboscidca is more closely marked than in 

 any other corresponding bones. The chief points of similar- 

 ity are : first, the subtriangular shape ; second, the same 

 relative proportions between the fossse ; third, the antro- 

 version of the spine ; fourth, the glenoid cavity looking di- 

 rectly down. The marked points of difference may be summed 

 up as, first, in the dissimilar proportion of the glenoid 

 cavity ; second, the great thickening of the spine at its 

 upper and lower extremities; third, in the high, shallow 

 acromio-scapular notch ; fourth, in the longitudinal concav- 

 itv of the internal surface. 



Mcas2ireinents. 



M. 



Extreme length of scapula -42 



Extreme length of spine -31 



Extreme thickness of spine at upper margin -098 



Extreme height of spine 1 • 109 



Basal width of proximal end of spine 032 



