Sternocleidomastoid branches of occipital artery

The sternocleidomastoid branches of occipital artery (sternocleidomastoid artery) generally arises from the occipital close to its commencement, but sometimes springs directly from the external carotid.

It passes downward and backward over the hypoglossal nerve, and enters the substance of the muscle, in company with the accessory nerve.