Mollusc radula. Light micrograph of a snail (Lathina rotundata) radula. The radula is a toothed chitinous organ in the mouth of gastropods, which, like a file, has central teeth to rasp off the surface of a plant, whilst the outer ones shear off hairs and other extrusions. Many plant surfaces are covered in abrasive cilia that wear the teeth away but these are replaced by new teeth produced at the back of the radula. This snail radula is unusual because the teeth are like hooks and are extremely large. They are likely to be capable of scrapping away the tough surface of some tropical plants.