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HEALTH AND DISEASE 



the size of the opening, as may be seen in the act of drinking. A 

 similar muscle (orbicularis pcdpebrarum) surrounds the eyelids, which it 

 closes. 



Besides these there are others much larger and stronger, one forming 

 the anterior part of the cheeks (buccinator and caninus). These are 

 attached to the upper and lower jaw, along the margins of the sockets 

 which contain the fangs of the molar teeth. When in action they throw 

 the food out of the channel of the cheek on to the grinding surface of the 

 teeth. 



Other muscles in this region are engaged in dilating the nostrils, and 

 thus ministering to the function of respiration. 



