THE MUSCLES. 67 



MUSCLES WHICH APPEAR ABOUT THE ANTERIOR PART OF THE 



NECK. 



Platysma moyoides arises from the cellular membrane covering 

 the pectoral and deltoid muscles. Inserted into the side of the 

 chin and integuments of the cheek. Use To draw the cheeks 

 and skin of the face downwards. 



Sterno-cleido-mastoideus arises from the upper part of the sternum, 

 and fore part of the clavicle. Inserted into the mastoid process 

 and as far back as the occipital suture. Use To move the head to 

 one side, and bend it forwards. 



MUSCLES SITUATED BETWEEN THE LOWER JAW AND OS HYOIDES. 



Digastricus arises from a fossa at the root of the mastoid process, 

 inserted into the lower and anterior part of the chin. ,Use To 

 draw the lower jaw downwards. 



Mylo-hyoideus rises from the inner surface of the jaw-bone. In- 

 serted into the basis of the os hyoides. Use To move the os 

 hyoides upwards. 



Genio-Hyoideus arises from the inside of the chin. Inserted into 

 the basis of the os hyoides. Use To move the os hyoides up- 

 wards. 



Genio-Glossus arises from the inside of the chin. Inserted into 

 the tongue, forming part of its substance. Use To move the 

 tongue in various directions. 



Hyo-glossus arises from the horn, basis, and cartilage of the os 

 hyoides. Inserted info the tongue laterally. Use To draw the 

 tongue downwards and inwards. 



Lingualis arises from the root of the tongue laterally. Inserted 

 into the extremity of the tongue. Use To shorten and draw the 

 tongue backwards. 



MUSCLES SITUATED BETWEEN THE OS HYOIDES AND TRUNK. 



Sterno-hyoideus arises from the sternum and clavicle. Inserted 

 into the basis of the os hyoides. Use To draw the os hyoides 

 downwards. 



Omo-hyoideus arises near the coracoid process of the scapula. 

 Inserted into the basis of the os hyoides. Use To draw the os 

 hyoides downwards. 



Sterno-thyroideus arises from the upper and inner part of the 

 sternum. Inserted into the thyroid cartilage. Use To pull the 

 thyroid cartilage downwards. 



