Posterior sclera, choroidea, retina
Transverse section through the sclera and choroidea of the eye of a pigeon (HE)
The choroid can be divided in: the suprachoroidea (lamina suprachoroidea), a stromal layer (lamina vasculosa) with prominent blood vessels, the choriocapillaris (lamina choroidocapillaris) and Bruchâ€™s membrane (lamina basalis choroidea). The suprachoroidea consists of large lacunae and the membrana fusca, a pigmented tissue layer between the sclera and lacunae.
At the micrograph above, the lamina suprachoroidea is destroyed (visible as one big artefact), the membrana fusca cannot be seen and Bruchâ€™s membrane is not present (attached to the retinal layer).