ORGANS OF SENSE. 167 



"brae; c, lachrymal gland ; o?, its division into two lobes; e, excretory ducts 

 of the lachrymal gland ; f^ their openings ; </, conjunctiva ; A, Meibomian 

 glands ; ^, superior punctum lachrymale ; /c, Meibomian glands of the lower 

 eye-lid ; l^ inferior punctum lachrymale ; ?w, caruncle. Fig. 5, nearly the 

 same view, but magnified: a, orbicularis muscle; Z), rima ; c, levator palpe- 

 brae ; /, openings of the excretory ducts of the lachrymal glands ; g^ conjunc- 

 tiva ; A, Meibomian glands of the upper eye-lid ; z, portion of the conjunctiva 

 reflected, to lay bare the Meibomian glands; /c, openings of these glands; 

 Z, glands of the lower eye-lid. Fig. 6, Meibomian glands, highly magnified. 

 Fig. 7, inside of the eye-lids, with the puncta lachrymalia. Fig. 8, lachry- 

 mal apparatus : a h c d^ upper and lower lachrymal canals ; e/^, lachrymal 

 sac ; h i, nasal portion of the lachrymal sac ; k I, lachrymal glands. Fig. 9, 

 muscles of the left eye-ball : '■ °' \ outline of the orbit ; \ pulley for the tendon 

 of the trochleator or superior oblique muscle ; *, eye-ball ; "'', optic nerve ; 

 a to e, levator palpebral superioris ; / g, superior, h i k, external rectus ; 

 ?, inferior oblique ; w., inferior rectus ; n o, internal rectus ; p to s, superior 

 oblique muscle of the eye. Fig. 10, the same view, the levator palpebrse 

 removed : °' ', optic nerve ; ^, superior rectus removed ; h to o, the same as 

 in the preceding figure ; p to u, superior oblique muscle. Fig. 11, a b c^ 

 internal rectus ; d ej] inferior, g h ?', external rectus ; k I m, inferior oblique 

 muscle. Fig. 12, nerves belonging to the eye : *, optic nerve ; ', third cere- 

 bral nerve or oculomotor ; cc, branch from it to the internal rectus muscle ; 

 *, fourth cerebral nerve ; a, branch from the fifth pair ; ^ fifth cerebral nerve ; 

 A, central extremity ; B, plexiform swelling; c, first branch ; D, second do. ; 

 E, third do. ; ff, foramen ovale ; G, foramen rotundum ; a, communicating 

 branch between the fourth and fifth nerves ; h to /, frontal branches ; ktoy, 

 distribution of the lachrymal nerve ; ^' °'' ^", sixth cerebral nerve. Fig. 13, 

 ramifications of the third pair of nerves, and the ciliary ganglion: A, supe- 

 rior rectus muscle ; B, B, levator palpebras ; ', third cerebral nerve ; a b, small 

 upper branch ; c, branch to the superior rectus ; d, branch to the levator 

 palpebrae ; e, inferior branch ; / branch to the inferior rectus ; ^, lower 

 branch ; h, branch to the ophthalmic ganglion ; ii, branches to the inferior 

 oblique muscle ; kkk III m, branches proceeding from the ophthalmic gan- 

 glion (ciliary nerves) ; \ fifth cerebral nerve ; oi, first branch ; o p q r, four 

 branches of the latter ; t, branch to the nares ; u, thread connecting it to the 

 nerve of the superior rectus ; v, branch to the ophthalmic ganglion ; ^ w, sixth 

 cerebral nerve. Fig. 11, nerve of the inferior rectus muscle; branch from 

 the fifth and sixth pairs to the nares : A, fifth cerebral nerve ; b, Casserian 

 ganglion ; c, first, d, second, e, third branches of do, ; F, F, lesser portion ; 

 G, superior oblique muscle ; b to v, the same as in the preceding figure ; 

 te, inferior trochleator nerve; a, sixth cerebral nerve; ßß, branches of 

 the sixth nerve to the carotid plexus ; % branch to the external rectus. 

 Fig. 15, ramifications of the left ophthalmic artery : a to D, orbit ; E, leva- 

 tor palbebraa, cut through and reflected ; F G, superior rectus ; H, internal 

 , rectus ; K, external rectus ; L, optic nerve ; M, eye-ball ; N o P, carotid 

 artery ; Q R, ophthalmic artery ; a b, ciliary arteries ; c, artery to the lachry- 

 mal gland ; d, ciliary branch of do. ; e, feeble branch to the external rectus ; 



873 



