The epithelium lining the branching ciliary processes shows the basal pigmented cells (P) applied to the underlying connective tissue. This tissue shows many small vessels (V).

The superficial non-pigmented epithelial cells (S), facing the posterior chamber of the eye, are associated with a thin PAS-positive layer (red arrowheads) which corresponds to a basement membrane (collagen type IV).

This basement membrane serves as the insertion site of zonular fibres (Z). These zonular fibres are also PAS-positive.

The ciliary body and processes are sites of production of aqueous humour.

Stain: PAS-Hematoxylin
Magnification: ×1000