THE MUSCULAR SYSTEM. 133 



They are attached to the perichondrium, periosteum, ligaments, 

 and subcutaneous tissue by a mutual interlacement of fibres. 

 Names of Muscles. They have received their names : 



1. From the arrangement of their fibres they have received the 

 names of radiated, penniform, bipenniform, etc. 



2. From their uses they are called extensors, adductors, etc. 



3. From their direction, oblique, rectus, transversalis, etc. 



4. From the number of insertions, as triceps, biceps, etc. 



5. From their form, as rhomboid, deltoid, etc. 



6. From their attachment, as occipito-frontalis, sterno-hyoid, etc-. 



The origin refers to the fixed extremity; the insertion, to 

 the movable point. 



MUSCLES OF THE HEAD. 



CRANIAL REGION. 



OCCIPITO-FRONTALIS. Origin, by two bellies, one from 

 outer two-thirds of superior curved line of the occipital bone 

 and base of the mastoid process of the temporal, the other from 

 corrugator supercilii, orbicularis palpebrarum, and pyramidalis 

 nasi fibres; insertion, into fibrous aponeurosis covering the ver- 

 tex of the skull ; action, raises the eyebrows and used chiefly as a 

 muscle of facial expression; nerves, supraorbital, small occipital, 

 facial, and posterior auricular branch of facial. 



AURICULAR REGION. 



ATTOLLENS AUREM. Origin, from aponeurosis of occipito- 

 frontalis ; insertion, into the surface of the pinna ; action, raises 

 the ear; nerve, occipitalis minor. 



ATTRAHENS AUREM. Origin, from edge of occipito-fron- 

 talis aponeurosis; insertion, into anterior part of helix; action, 

 draws the ear upward and forward ; nerve, facial. 



RATRAHENS AUREM. Origin, from mastoid portion of tem- 

 poral bone; insertion, into lower part of concha; action, draws 

 the ear backward ; nerve, posterior auricular branch of facial. 



PALPEBRAL REGION. 



ORBICULARTS PALPEBRARUM. Origin, from nasal process of 

 superior maxilla, internal angular process of frontal, and from 

 front and sides of tendo-palpebrarum ; insertion, into skin of 

 the cheek, eyelids, forehead, and temple, blending with the cor- 

 rugator super-oil ii and the occipito-frontalis; action, sphincter of 

 the eyelids ; nerve, facial. 



