Fly's tongue, coloured scanning electron micrograph (SEM). Flies do not have a muscular tongue like humans, but the tip of their proboscis has a similar sensory function. This is the labellum, one of a pair of pads on the proboscis' tip that is responsible for distinguishing tastes.This view shows the ducts which carry digestive enzymes along the tongue. The enzymes are used to pre- digest food, which is then 'mopped' up by the labella in liquid form. Research has shown that flies are able to taste a wide variety of flavours, and are especially adept at distinguishing between bitter flavours. Magnification: x800 when printed at 10cm wide.