The Diagnosis of the Diseases of Poultry 43 



bones. This girdle consists of the shoulder blade or scapula 

 (9), the coracoids (11), and the "wishbone" or furcula (10). 

 In young birds the furcula consists of separate paired bones, 

 the clavicles, and the small median ossification, the inter- 

 clavicle. 



The icings include the upper arm, the forearm, the wrist, 

 the hand, and the fingers. The upper arm bone, or humerus 

 (12), is a single strong bone of the same length as the bones 

 of the forearm. The forearm (13) contains two bones, the 

 radius and the ulna. The wrist has only two bones not 

 distinguishable in the figure. The hand (14) is made up 

 from two bones which are united at both their upper and 

 lower ends, but separated in the middle. In front of the 

 larger of these two is the small one-jointed finger, the so- 

 called thumb (15). The second finger (16), which is the 

 longest and strongest, has two joints ; the third finger is 

 one-jointed. 



The bones of the leg are homologous with those of the 

 wing. The bone of the thigh, the femur (22), is a single 

 bone. The lower leg (24), which in the normal position of 

 the bird extends backwards and downwards from the knee 

 (23), consists like the forearm of two bones: a large tibia 

 and a very small splint-like bone, the fibula. At (25) is 

 the hock or ankle joint. Below this come the bones of the 

 foot. The first of these (26) is the tarso-metarsus. As an 

 outgrowth from this bone is the spur (31). Of the four toes 

 the inner or hind toe (30) has two joints ; the second or inner 

 front toe (29) has three joints ; the middle front toe (28) has 

 four ; and the outer front toe (27) has five joints. 



The Viscera 



The main features of the normal visceral anatomy of the 

 fowl are shown in Fig. 7, which represents a dissection from 



