The occipitalis muscle is thin and quadrilateral in form.

It arises from tendinous fibers from the lateral two-thirds of the superior nuchal line of the occipital bone and from the mastoid process of the temporal and ends in the epicranial aponeurosis.

[1] The occipitalis muscle is innervated by the posterior auricular nerve (a branch of the facial nerve) and its function is to move the scalp back.

[2] The muscles receives blood from the occipital artery.

This article incorporates text in the public domain from page 379 of the 20th edition of Gray's Anatomy (1918)