502 



MOVEMENTS OF THE PUPIL. [BOOK in. 



The iris is supplied, in common with the ciliary muscle and 

 choroid, by the short ciliary nerves (Fig. 68 s.c.) coming from the 

 ophthalmic or lenticular (ciliary) ganglion (I.e.) which is connected 

 by its roots with the third nerve (r.b.), the cervical sympathetic nerve 

 (sym.), and with the nasal branch of the ophthalmic division of the 



FIG. 68. DIAGRAMMATIC REPRESENTATION OP THE NERVES GOVERNING THE PUPIL. 



II. Optic nerve, l.g. lenticular ganglion, r.b. its short root from III. oc.in. third 

 or oculo-motor nerve. sym. its sympathetic root. r.l. its long root from 

 V. ophthm. the nasal branch of the ophthalmic division of the fifth nerve, 

 s.c. the short ciliary nerves from the lenticular ganglion. I.e. the long ciliary 

 nerve from the nasal branch of the ophthalmic division of the fifth nerve. 



fifth nerve (r.l.) The short ciliary nerves are, moreover, accompanied 

 by the long ciliary nerves (I.e.) coming from the same nasal branch 

 of the ophthalmic division of the fifth nerve. What are the uses 

 of these several nerves in relation to the pupil ? 



If the cervical sympathetic in the neck be divided, all other 

 portions of the nervous mechanism being intact, a contraction of 

 the pupil (not always very well marked) takes place, and if the 

 peripheral portion (i.e. the upper portion still connected with the 



