604 THE TISSUES. 



brane is reflected from the selerotica above and below, and lines 

 the lids. The latter also have a compound scaly epithelium. Pa- 

 pillae occur on the palpebral conjunctiva, especially towards the 

 line of reflection, where they are yj^ of an inch long. At the 

 line of reflection they are sometimes even ^ of an inch. (Krause.) 

 Their enlargement constitutes the granular lid, so called ; the lower 

 lid being most frequently affected, since they are most abundant 

 there. 



The eyelids consist of 1st, the mucous membrane just described; 

 Idly, the fibres of the levator palpebrse superioris, and the orbicu- 

 laris palpebrarum; and, Sdty, the skin, only 5 V to ^ of an inch 

 thick ; all these elements being connected together by a lax con- 

 nective tissue. The skin is furnished throughout with minute 

 sweat-glands ( T 2<T to T J^ of an inch), and generally with minute 

 hairs and sebaceous glands. The free borders of the lids are 

 bounded by the tarsi, improperly termed tarsal cartilages. They 

 consist merely of fasciculi of white fibrous tissue, though occasion- 

 ally containing a few minute cartilage-cells. Into their free edges 

 the cilia (eyelashes) are inserted, immediately in relation with the 

 Meibomian glands. (Fig. 133.) 



But for a full description of the remaining appendages of the 

 eye (the muscles and the lachrymal passages, &c.) the works on 

 descriptive anatomy may be consulted, since they present no pecu- 

 liar histological elements. For the very numerous pathological 

 conditions to which this organ is liable, reference must be had to 

 the special treatises on this subject. 



