SURFACE VIEW OF THE EYE 



1053 



conjunctiva known as the plica semilunaris. While the eye is open, press one finger on the skin, 

 a little beyond the lateral angle, and draw it firmly away from the middle line; observe that the 

 upper lid then falls over the eyeball, and that the outline of a firm band already referred to 

 (the medial palpebral ligament) becomes evident, passing between the medial angle and the 

 nose. The faUing of the lid is caused by our dragging upon a ligament (the lateral palpebral 

 raph^) to which the lateral end of its tarsus is attached, and so putting the lid itseK upon the 

 stretch. If, while the eyeball is directed downward, we place one finger on the lateral end of the 

 upper eyelid and draw it forcibly upward and laterall}', we can usually cause the lower division 

 of the lacrimal gland to present just above the lateral angle. 



Fig. 797. — View of the Eye with Eyelids Closed. 

 Sulcus orbitopalpebralis superior Angulus oculi medialis 



■■^v 



Cilia Palpebra 

 inferior 



Medial palpebral commissure 



The Upper eyelid [palpebra superior] is much broader than the lower, extending upward 

 as far as the eyebrow. The skin covering it is loosely attached to the subjacent tissues above, 

 but more firmly below, nearer the free margin, where it overlies a firm fibrous tissue called the 

 tarsus superior. When the eye is open, a fold is present at the upper border of this lower more 

 tightly applied portion of skin, called the superior palpebral fold, and by it the lid is marked off 

 into an upper or orbital, and a lower or tarsal, division. The presence of the tarsus can be 

 readily appreciated on our pinching horizontally the entire thickness of the eyehd below the 

 palpebral fold. The lower eyelid [palpebra inferior] is similarly divided anatomically into a 

 tarsal and an orbital part, but the demarcation is sometimes unrecognisable on the surface, 



Fig. 798. 



-View of Medial Region of the Eye, with the Eyelids Widely Separated 



AND the Ey'EBALL TuRNED LATERALLY. 



Edge of 

 palpebra superior 



Papilla 

 lacrimalis 



j^ Plica 



" >*. semilunaris 



--;^g.„Caruncula 

 lacrimalis 



Limbus 

 palpebralis 

 posterior 



Tarsal (Meibomian) glands 



though a fold or groove (the inferior palpebral) is usually visible when the eye is widely opened. 

 There is no precise limit of this lid below, but it maybe regarded as extending to the level of the 

 lower margin of the orbit. Numerous verj' fine short hairs are seen on the anterior surface of 

 both eyelids. Each eyelid presents an anterior and a posterior surface, separated by a free 

 margin with two edges: — (a) An anterior, rounded edge [limbus palpebralis anterior] along 

 which the stiff cilia, or eyelashes, are closely placed in a triple row; and (b) a sharp posterior 

 edge [limbus palpebralis posterior] which is applied to the surface of the globe (see fig. 813). 

 The cilia of both eyehds have their points turned away from the palpebral aperture, so that 

 the upper ones curve upward, and the lower downward; the cUia of the upper hd are the stronger. 



