Horizontal Section Of Right Eye
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The diagram depicts a cross section of an eyeball, looking to the left.
The following labels are visible:
* conjunctiva (transparent membrane for protection)
* cornea (transparent)
* iris
* pupil
* aqueous humour
* zonula (suspensory ligament)
* lens
* ciliary body (ring shaped muscle)
* lateral rectus muscle (rotation of eyeball)
* vitreous humour
* sclerotic coat (opaque, white of eye)
* choroid (blood vessels supplying food and oxygen)
* retina (see below)
* fovea
* blind spot
* optic nerve
* medial rectus muscle

The labels are placed in the following positions.

A thin film labelled CONJUNCTICA covers the front of the eyeball (left most
side of diagram). The CORNEA is a thick layer below the conjunctiva, which
seems to go all the way around the eyeball (it seems to act as the outer
wall in this diagram). However, at the back the same part of the eye is
labelled SCLEROTIC COAT. The sclerotic coat wraps round the back of the eye.
At the OPTIC NERVE (lower right of diagram) the SCLEROTIC COAT continues
around the optic nerve and seems to leave the eyeball.

Vertically centered on the horizontal axis but positioned one quarter of the
width from the left hand side is a bulge labelled LENS. The lens divides the
eye ball in two unequal parts. On the right hand side, the large empty area
is labelled VITREOUS HUMOUR. On the left hand side is a much smaller area,
labelled AQUEOUS HUMOUR.

Centered on the horizontal axis in front of the lens (to the left on the
diagram) is a gap between two relatively thin protrusions labelled IRIS. The
gap has a small double ended arrow showing it's diameter, which is labelled
PUPIL.

The top iris continues upwards until is has passed the lens, at which time
it enlarges considerably to be roughly the same width as the lens. At this
point it is labelled CILIARY BODY. It is a 'ring shaped muscle' since it
goes all the way around the lens (not visible on the diagram since it is a
cross section, but we do see the same shape below the lens). There is a
small gap between the lens and ciliary body, which is labelled ZONULA, that
is the suspensory ligament.

On the back (right of diagram) of the eyeball are several layers. Starting
from the vitreous humour, we have first the RETINA. The retina goes all the
way around the back of the eyeball, and has two dips. Centered on the
horizontal axis is a dip labelled FOVEA. At the bottom right corner of the
diagram is a much bigger dip with a double ended arrow at it's mouth. This
is labeled the BLIND SPOT, and is where the optic nerve leaves the eye.

The layer below the retina is the CHOROID. This is labelled as being blood
vessels which supply food and oxygen. Finally, the last layer is the
sclerotic coat.

Holding the top of the eyeball is a LATERAL RECTUS MUSCLE, which on the
diagram has the same width as the cornea. on the bottom is another muscle,
labelled MEDIAL RECTUS MUSCLE. The top muscle is labelled as being in charge
of rotation of the eyeball.

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