AND PHYSIOLOGY. 



377 



lages, directly in the substance of which is placed a large 

 quantity of minute glands, called Meibomian Glands. 



Fig. 351. 



Fig. 352. 



Meibomian Gland highly 

 magnified. 



Meibomian Glands seen from the Inner or Ocu- 

 lar Surface of the Eyelids, with the Lachrymal 

 Gland — of the Right Side, a, Palpebral Conjunc- 

 tiva. 1, Lachrymal Gland. 2, Openings of Lachry- 

 mal Ducts. 3, Lachrymal Puncta. 6, Meibomian 

 Glands. 



691. Muscles of the Eye.— The 

 Ball of the eye is moved by six distinct 

 muscles, four straight and two oblique 

 muscles, as is shown in the cut. Their 

 names are Rectus Superior and Inferior, External and Inter 

 nal, and Superior and Inferior Oblique. 



Muscles of the Eyeball. 1, A small FlG. 353. 



Fragment of the Sphenoid Bone 

 around entrance of Optic Nerve into 

 Orbit. 2, Optic Nerve. 3, Globe of 

 Eye. 4, Levator Palpebral Muscle. 

 5, Superior Oblique Muscle. 6. Its 

 Cartilaginous Pulley. 7, Its reflected 

 Tendon. 8, Inferior Oblique Muscle; 

 the small square knob at its com- 

 mencement is a piece of its bony 

 origin broken off. 9, Superior Pec- 

 tus. 10, Internal Rectus almost con- 

 cealed by Optic Nerve. 11, Part of External Rectus, showing its two heads 

 12, Extremity of External Rectus, at its Insertion; the intermediate portion 

 having been removed. 13, Inferior Rectus. 14, Tunica Albuginea formed by 

 of tendons of four recti. 



of origin, 

 of muscle 

 expansion 



691. How many muscles for moving the eyeball ? Give their names. 



