In the eye of the bird a comb like structure is present. It is called pecten. It is soft and vascular. It is a rectangular plate. It projects into the vitreous humour from the blind spot.
Functions of pecten :
1) It protects the retina from sunlight by casting shadow on it.
2) pecten gives additional nourishment to the retina.
It exists pressure on the lens and alter its curvature for accommodation.