960 THE JOHN DAY FAUNA. 



The head of the humerus presents some characters which distinguish it 

 from those of the sjjecies of cats above mentioned, although it resembles 

 them strongly in general features. While rather smaller than those of 

 the panther and leopard, the greater tuberosity is more prominent, and 

 the bicipital groove wider and deeper. The proximal surface of the lesser 

 tuberosity is more distinct from the head, and is less decurved posteriorly. 

 Viewed from the inner side its proximal surface is nearly straight and 

 makes a right angle with the prominent posterior bicipital crest instead of 

 being continuous with it, as in the panther and domestic cat, more nearly 

 resembling the leopard and the lion. The tricipital fossa is larger than in 

 any of those species, being well defined b}^ a strong ridge posteriorly. 

 The fossa musculi teris is quite small, less than in the Uncia concolor and 

 U. ho and Felis domesfica. The distal extremity of the humerus displays 

 characters intermediate between those of the existing Felidce and the fiesh- 

 eaters of the Eocene period. This is shown in its rather greater transverse 

 extent; or, to particularize, in the greater length of the radial part of the 

 trochlea and greater production of the internal epicondyle. The former 

 has its proximal anterior border notched, and its face has a corresponding 

 slight contraction not seen in any of the recent Felidce, but not quite as 

 strong as that of the Crocuta brunnea and the Canidce. The distal extremity 

 of the internal epicondyle is a truncate half-circle. Its production interior 

 to this is withdrawn to a more proximal position. The olecranar fossa i& 

 well marked, and has a slight perforation. The radial fossa is w^anting. 



The Jifth metacarpal is, relatively, smaller than in Uncke ho, pardus, and 

 concolor, Cyncelurus jubatus and Fells domestka. It displays all the special 

 characters of these species, including the keel-like interlocking process con- 

 necting it with the fourth metacarpal, so characteristic of the FeUdce. The 

 proximal extremity resembles that of the lion rather than that of the pan- 

 ther in the plane surfoce of insertion of the external articular ligament. 



Measurements of fore limb, 



ji. 



Diameters of glenoid cavity of scapula I anteroposterior 0-J9 



( transverse at middle (_m 



{transverse, extreme 049 

 transverse to groove U33 

 through lesser tuberosity 036. 



