ORGANS OF SPECIAL SENSE. 



343 



Nerves are: 



Olfactory, or first cranial, the special nerve of smell, is dis- 

 tributed over the upper third of the septum, and superior turbin- 

 ated bones. 



Anterior dental branch of superior maxillary to the inferior 

 turbinated bone and inferior meatus. 



Nasal branch of ophthalmic, to the outer walls and septum. 

 Besides these, the spheno-palatine ganglion., the vidian, the supe- 

 rior nasal branch, naso-palatine, and anterior palatine also send 

 branches to the parts. 



Horizontal section of right orbit. 1, Homer's muscle; 2, septum or- 

 bitale; 3, fibres of the orbicularis palpebrarum muscle; 4, tarsal plate; 

 5, conjunctival sac; 6, outer palpebral ligament; 7, temporal muscle; 

 8, wall of the orbit; 9, external rectus muscle; 10, orbital fat; 11, optic 

 nerve; 12, internal rectus muscle; 13, inner check ligament; 14, inner 

 wall of the orbit; 15, attachment of the capsule of Tenon (16) to the 

 conjunctiva; 17, Tenon's space; 18, outer check ligament; 19, lachrymal 

 gland; 20, ciliary process; 21, iris. (After Gerlach.) (Ball.) 



THE EYE. 



THE ORGANS OF SIGHT comprise the eyeballs and their ap- 

 pendages and the optic nerves. 



The eye is a spherical organ, situated in the anterior part 

 of the skull, protected in front by several appendages, acted upon 

 by muscles, and supplied by blood-vessels and nerves. 



Within the orbit it rests upon a bed of fat, from which it is 

 separated by a membranous sac the capsule of Tenon. 



