(b) : Each half of pectoral girdle is made up of two bones scapula and clavicle. At the outer angle of scapula is a shallow socket known as glenoid cavity into which fits head of humerus bone to form a shoulder joint. Above glenoid cavity project two processes - acromion process and coracoid process. Acromion process extends over the glenoid cavity and articulates with clavicle to form shoulder girdle. Coracoid process is like a hook and is smaller than acromion process.