former is attached to the anterior border of the manubrium, the latter to its posterior border and to the interclavicular ligament.

Between these two layers is a slit-like interval, the suprasternal space (space of Burns); it contains a small quantity of areolar tissue, the lower portions of the anterior jugular veins and their transverse connecting branch, the sternal heads of the sternocleidomastoid, and sometimes a lymph gland.