68 ANATOMY. 



Describe each Muscle of the Body, giving its Origin, Insertion, Action, 

 and Nervous supply. 



MUSCLES OF THE HEAD. 

 Occipito-frontalis," from the external two-thirds of the superior curved line 



of the occipital bone and the mastoid process of the temporal; also from the 



pyramidalis nasi, corrugator supercilii, and orbicularis palpebrarum fibres, 



into an aponeurosis or "galea capitis," which covers the vertex of the skull. 



Action, chiefly as a muscle of facial expression. Nerves, facial, supraorbital, 



small occipital. 

 Attollens Aurem, from the occipito-frontalis aponeurosis, into the pinna of 



the ear superiorly. Action, to raise the pinna. Nerve, small occipital branch 



of the cervical plexus. 

 Attrahens Aurem, from the lateral cranial aponeurosis, into the helix of the 



ear anteriorly. Action, to draw the pinna forwards. Nerves, facial, and 



auriculo-temporal branch of the inferior maxillary. 

 Retrahens Aurem, from the mastoid process of the temporal bone, into the 



concha. Action, to retract the pinna. Nerve, facial. 

 Orbicularis Palpebrarum, from the internal angular process of the frontal bone, 



the nasal process of the superior maxillary, and the borders of the tendo 



oculi, into the skin of the eyelids, forehead, temple, and cheek, blending 



with the occipito-frontalis and the corrugator supercilii. Action, to close the 



eyelids. Nerve, facial. 

 Corrugator Supercilii, from the inner end of the superciliary ridge of the 



frontal bone, into the orbicularis palpebrarum. Action, to draw eyebrow 



downwards and inwards. Nerve, facial. 

 Tensor Tarsi (Horner's muscle), from the crest of the lachrymal bone, into 



the tarsal cartilages by two slips. Action, to compress the puncta lachry- 



malia against the globe of the eye, and to compress the lachrymal sac. 



Nerve, facial. 

 Levator Palpebrae Superioris, from the lesser wing of the sphenoid, into the 



upper tarsal cartilage. Action, to lift the upper lid. Nerve, 3d cranial, or 



motor oculi. 

 Rectus Superior, from the upper margin of the optic foramen and the sheath 



of the optic nerve, into the sclerotic coat. Action, to rotate the eyeball 



upwards. Nerve, 3d cranial. 

 Rectus Inferior, from the ligament of Zinn, into the sclerotic coat. Action, 



rotates the eyeball downwards. Nerve, 3d cranial. 

 Rectus Internus, from the ligament of Zinn, into the sclerotic coat. Action, 



rotates the eyeball inwards. Nerve, 3d cranial. 



