Perhaps no one of the insectivorous plants possesses what may be more truly called a trap than does the bladderwort (Utricularia). This is a floating aquatic plant without roots, confined to pools and quiet streams where it is in no danger of being washed away. Borne thickly upon the fine leaves, and like them entirely submerged in the
water, are the traps, minute hollow globular structures bristling with hairs at one end. Buried among the hairs is the entrance to the trap. Swimming about in search of food or in an attempt to escape from enemies, some minute crustacean or insect larva will push in among the hairs. Spying the entrance, it will dart forward and striking the almost transparent door it will unwittingly pass into the trap. But the door has instantly sprung shut again and vain will be all the efforts of the prisoner to make an escape. Starvation soon ends its struggles.