94 THE EYE AND EAR. 
ii. The choroid: the dense black coat exposed by the 
removal of the sclerotic. 
il. The ciliary vessels: these pierce the sclerotic to 
convey blood to and from the choroid, which is 
extremely vascular. 
iv. The ciliary nerves: seen passing through the 
sclerotic to the choroid while the flaps are being 
turned down, 
4. Make a couple of radial incisions a short distance apart 
through the wris and ciliary muscle, and turn back the portion of 
the ures between the two cuts: note :— 
i, The ciliary processes; a series of radial folds on 
the under surface of the outer margin of the iris: 
they fit into corresponding folds in the ligament 
which surrounds and supports the lens. 
5. Make a circular incision with scissors all round the eye about 
half an inch behind the ciliary muscle, cutting through the choroid 
and retina, but taking care not to injure the delicate membrane 
enclosing the vitreous humour. Gently detach and remove in one 
prece this front ring of iris, choroid, and retina: pin tt on the 
dissecting board with the posterior surface upwards : note :— 
i. The ciliary processes. 
ii, The uvea: the layer of dense black pigment at 
the back of the iris. 
iii, The ora serrata: the indented anterior boundary 
of the part of the retina sensitive to light: 
in front of this the retina becomes extremely 
thin, but really extends forwards as far as the 
free edge of the iris. 
6. Hxamine the front of the eyeball from which the ring has been 
removed as described above: note :— 
i. The capsule of the lens: transparent and elastic. 
ii. The suspensory ligament of the lens, or zonule of 
Zinn: the outer margin of the capsule of the 
lens: marked with radiating folds into which 
the ciliary processes fit. 
