The last 2 pairs (11^th and 12^th) of ribs are not connected ventrally to the sternum and are, therefore, called floating ribs.

Each half of the pectoral girdle consists of a clavicle and a scapula. The scapula is a large triangular flat bone situated in the dorsal part of the thorax between the second and the seventh ribs. The dorsal, flat, triangular body of the scapula has a slightly elevated ridge called the spine which projects as a flat, expanded process called the acromion which forms the highest point of shoulder. The clavicle articulates with this. Below the acromion is a depression called the glenoid cavity which articulates with the head of the humerus to form the shoulder joint. Each clavicle is a long slender bone with two curvatures. This bone is commonly called the collar bone.