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ELEMENTARY PHYSIOLOGY 



The first pair are the olfactory nerves or the nerves of smell. These are 

 the sensory or afferent nerves, the fibres of which are supplied to the mucous 

 lining of the nose. 



The second pair are the sensory nerves of the eye the optic nerves, or 

 nerves of sight. 



The third pair are called the motores oculi (movers of the eyes). They 

 are distributed to some of the muscles which move the eyeballs. 



The fourth, pair are motor nerves. They supply one of the muscles of the 

 eyes. 



The fifth pair are very large nerves, containing both motor and sensory 

 fibres. Each one divides into three branches, and they are consequently called 



Fig. 169. The Cranial Nerves of the Left Side. 



the trigeminal nerves. They supply the skin of the face, the muscles of the 

 lower jaw,- and the tongue. 



The sixth pair are supplied to the muscles which turn the eyeballs out- 

 wards. Thus the muscles of the eye receive nerve fibres from three distinct 

 pairs of nerves the third, fourth, and sixth. 



The seventh pair are called the facial nerves, since they supply fibres to 

 the muscles of the face. 



The eighth pair are the auditory nerves the sensory nerves which 

 supply the ear. 



The ninth pair are mixed nerves, called the glossopharyngeal (Gr. glossa, 



