32 THE STRUCTURE OF THE FOWL 



The ischium is much smaller than the ilium, 

 and, in the adult, continuous therewith except 

 at a large, ovoid opening, the sciatic foramen. 



The pubis is a thin and nan-ow strip of bone 

 running along the border of the ischium to 

 which it is joined for a short distance only. 

 The free posterior end of the pubis projects 

 backwards for a little distance beyond the 

 ischium, while its anterior end forms a short 

 projection in front of the acetabulum. Close 

 to the acetabulum an oval obturator' foramen 

 separates the pubis and ischium. 



The relatively large and deep acetabulum is 

 pierced by a large foramen and receives the head 

 of the femur. Immediately above the acetabu- 

 lum a projection of the ilium carries an articular 

 surface for contact with the femoral trochanter. 



The stout, cylindrical, and somewhat bent 

 femur has a prominent head at its proximal 

 extremity. The head is much too small to 

 fill the acetabulum completely, with the result 

 that the articular surface of the femur extends 

 beyond the head on to the trochanter — an 

 irregular projection lateral to the head. The 

 distal end carries a deep, pulley-shaped surface 

 for the patella, or knee-cap, and two convex 

 condyles for articulation with the bones of the 



