EYEBALL. 65 
Describe the suspensory ligament. 
It is a delicate fibrillated membrane attached on the one hand to a 
membrane covering the ‘ciliary processes, and on the other to the cap- 
sule of the crystalline lens, which is suspended by it just behind the 
iris. 
Describe the chambers of the eye. 
Histologically, the eye is divided into an anterior and posterior 
chamber by the crystalline lens and suspensory ligament. The anterior 
chamber contains a homogeneous fluid called the aqueous fluid, and 
the posterior a gelatinous mass called the wtreous body. Ophthalmol- 
ogists, however, call the portion between the cornea and the iris the 
anterior chamber, and that between the iris and crystalline lens the 
posterior chamber 
Describe the structure of the vitreous body. 
It is a gelatinous, ill-defined lamellar structure gontaining a variable 
number of ill-defined, granular cells. It is surrounded by a delicate 
membrane called the hyaloid membrane. It is connected posteriorly 
with the retina, from which it is difficult to differentiate. This mem- 
brane is thickened and fibrillated over the ciliary process, where it is 
called the zonula ciliaris. A prolongation of it forward goes to make 
up the suspensory ligament of the lens. 
What is the structure of the sclera ? 
It is made up of closely-woven fibrous tissue, between the fibres of 
which are scattered flattened cells, some of which may contain pigment. 
On its external surface delicate fibres are given off anteriorly to the 
subconjunctival tissue, posteriorly behind the muscle tendons they 
join to form the wall of a lymph sac (capsule of Tenon). On the 
inner wall fibres pass to the choroid coat, some of which help to form 
the outer wall of a lymph sac between the sclerotic and choroid, 
called on account of its color the damina fusca. The opening for the 
entrance of the optic nerve in the posterior segment of the sclerotic is 
covered by a network of connective-tissue fibres called the lamina 
eribrosa. 
Describe the cornea. ‘ 
It is directly continuous with the sclerotic, but differs from it in 
that its fibres are clearer and more regularly arranged. Its free sur- 
faces are covered with epithelium and its cellular elements are peculiar 
in form. It consists of five separate layers. 
5—H.P.B. 
