 The bumblebee tongue ( the proboscis ) is a long , hairy structure that extends from a sheath @-@ like modified maxilla . The primary action of the tongue is lapping , that is , repeated dipping of the tongue into liquid . The tip of the tongue probably acts as a suction cup and during lapping , nectar may be drawn up the proboscis by capillary action . When at rest or flying , the proboscis is kept folded under the head . The longer the tongue , the deeper the bumblebee can probe into a flower and bees probably learn by experience which flower source is best @-@ suited to their tongue length . Bees with shorter <unk> , like Bombus <unk> , have a more difficult time foraging nectar relative to other bumblebees with longer <unk> ; to overcome this disadvantage , B. <unk> workers were observed to lick the back of spurs on the nectar duct , which resulted in a small reward . 
