240 THE SHOULDER GIRDLE. [chap. xiv. 



Mammal, called interclavicle. Its lower end is broad, and 

 rests on the expanded straight upper margin of the pre- 

 sternum ; it contracts somewhat above, before dividing into a 

 pair of nearly horizontal, slightly curved arms, which extend 

 outwards towards, though not quite reaching, the acromion. 

 This bone differs from the presternum, and the small proosteal 

 plate behind its lower extremity, as well as the coracoids 

 and epicoracoids, in being developed in membrane. 



The clavicles (r/) are simple, elongated, slightly curved, 

 thin, splint-like bones, resting upon the anterior surface of 

 the arms of the interclavicle, pointed and not quite meeting 

 internally, and dilated and articulating directly with the 

 acromion at their outer end. 



