64 THE SKELETON OF THE CAT. 



midway between the tip of the acromion and the vertebral end 

 of the spine. The spine is inclined toward the glenoid margin 

 so as to form an angle of about 60 degrees with the caudal half 

 of the lateral surface. 



At the base of the acromion process {J) the margin of the 

 spine presents a flat triangular projection, the metacromion (/), 

 directed toward the glenoid border. 



The acromion (J) continues in the direction of the spine. 

 It is thicker than the spine, smooth and rounded on both its 

 surfaces and both its borders, and its apex is connected by 

 fibrous tissue to the clavicle. 



The coracoid border {b) presents a slight rounded notch, 

 the incisura scapulae or suprascapular notch (/), just dorsad of 

 the glenoid angle, and at its ventral end bears the coracoid 

 process (;;/) which is directed ventromediad. 



The glenoid angle {d) is the only one requiring special 

 mention. Between the root of the coracoid process and 

 the glenoid cavity it presents a tubercle, the supraglenoidal 

 or bicipital tubercle (^k), for the tendon of origin of the biceps 

 muscle. The glenoid angle is separated by a contracted neck 

 from the rest of the bone. Between this angle and the inner 

 margin of the acromion there is left a deep notch, the great 

 scapular notch. 



Clavicle. Clavicula (Fig. 46). — The clavicle in the cat is 



__,___^^__ greatly reduced. It is a slender curved rod 



h^^' ^^"-^^ a of bone imbedded in the muscles of the 



Fig. 46.— Clavicle, shoulder and connected by fibrous tissue to 



a, medial end; b, lat- the apex of the acromion process. The 



"^^ ^"'^- lateral end {b) is slightly enlarged. 



Humerus (Figs. 47 and 48). — The humerus forms the sup- 

 port of the upper arm and' articulates by its proximal end with 

 the scapula at the glenoid cavity, and by its distal end with the 

 radius and ulna, the bones of the lower arm. It is a nearly 

 cylindrical bone with enlarged ends, and is so curved that its 

 dorsal and ventral borders are hooked at the opposite ends so 

 that it has the form of an Italic f. 



The proximal end of the bone bears on its dorsomedial 

 portion a thickening, the head of the humerus {a), which bears 



