<P> The molluscs have the widest variety of eye morphologies of any phylum, and a large degree of variation in their function . Cephalopods such as octopus, squid, and cuttlefish have eyes as complex as those of vertebrates, while scallops have up to 100 simple eyes . </P> <P> There are between seven and eleven distinct eye types in molluscs . Molluscs have eyes of all levels of complexity, from the pit eyes of many gastropods, to the pinhole eyes of the Nautilus, to the lensed eyes of the cephalopods . Compound eyes are present in some bivalves, and reflective' mirrors' have been innovated by other lineages such as scallops . As well as varying in complexity, the eyes of molluscs span a huge range in size; they may be from 20 μm (0.02 mm) to 27 cm (11 in) across . </P> <P> Gastropods and cephalopods have paired eyes on their heads (and sometimes tails), but many molluscs do not have clear head regions in which to locate the eyes . Consequently, many molluscs may have a multitude of eyes in more unlikely places, such as along the edge of their shell . Chitons have a dispersed network of tiny eyes over the surface of their shells which may act together as a compound eye . Many gastropods have stalked eyes; the eye can be retracted into the stalk itself in the presence of danger . </P>

Which mollusk has the largest eye of all animals