. ...and so the insect falls into a pool of liquid at the bottom of the tube and is drowned. The pool of liquid doesn't show here because in sectioning the leaf, the liquid drained out. But you can see the bodies of dead insects that have been trapped by this particular leaf. The soft parts of the insects are digested and turned into nitrogen compounds that are used by the plant. Darlingtonia, like other carnivorous plants, grow in water that is poor in nitrogen, and the soft parts of insects are rich in nitrogen and can supply the nutritional need to the plant. The hard surfaces of insects cannot be digested and remain in the leaf.