744 



THE NERVOUS SYSTEM 



as surely paralyse the facial and hypogloss^al nerves as if the nuclei of tliese nervet; 

 had been dt^stroyed in the medulla. 



General distribution. — The olfactory, optic, and auditory nerves are exclu- 

 sively nerves of special sensi', and are distributed to the nose, the eye, and the ear, 

 res}X'ctively. Of the reniaininoj nerves, some are motor, others are mixed. The 

 motor nerves are: the third, fourth, and sixth to the ocular muscles, the seventh 

 to the i>hitysma and to the superticial muscles of the face and scalp, and the twelfth 

 to the muscles of the tongue. The mixed are the fifth, which is chiefly sensory to 

 the face, teeth, eye, external ear, and fore part of the scalp, but also motor to the 

 muscles of mastication; the ninth, which contains fibres for the special sense of 



Fit;. 441. — ScRFACE Okkun' of the Ceaxiai, Nerves. 

 (After Allen Thomson. — Quain.) 



OPTIC THALAMUS 



OPTIC TRACT 

 TUBER CINEREUM 



POSTERIOR PER- 

 FORATED SPACE 

 CORPUS GEXICU- 



LA TUM EXTERXUM 

 CORPUS GEXICU- 



LA TUM INTERNUM 



PYRAMIDAL BODY 

 OLIVARY BODY 



ARCIFORM FIBRES 



FIRST CERVICAL NERVE 



ANTERO-LATERAL GROOVE 

 OF SPINAL CORD 

 ANTERIOR COLUMN OF 

 SPINAL CORD 



ISLAND OF REIL 



PITUITARY BODY 



CORPORA 

 ALBICANTIA 



CPUS CEREBRI 



PONS VAROLII 



GREA T HORIZONTAL 



FISSURE 

 FLOCCULUS 



FORAMEN CMCUM 



SPINA L A CCESSOR Y 

 NER VE 



taste, also ordinary sensory and motor fibres; the tenth, wliich conveys sensory 

 fibres to the external ear, and both motor and sensory fibres to the jdiarynx, larynx, 

 heart, lungs, trachea, oesophagus, and stomach; and the eleventh, which divides 

 into a spinal part, wholly motor, destined for the sterno-mastoid and trapezius 

 muscles, and a mixed or accessory part w'hich joins the tenth. 



In the following pages the course of each nerve is described in order from its 

 so-called deep origin to its peripheral distribution; the ultimate connection with 

 the cortex is described in the anatomy of the brain. An exception is made, how- 

 ever, in the case of the olfactory and optic nerves, the cerebral connections of 

 which are described with the nerves. 



