I never paid any attention to these plants until they were pointed out to me. I knew of them but that was about all.
Pitcher plants are carnivorous plants which have modified leaves known as pitfall traps—a prey-trapping mechanism featuring a deep cavity filled with digestive liquid. The traps of what are considered to be “true” pitcher plants are formed by specialized leaves. The plants attract and drown their prey with nectar. (Wikipedia).
Of course now that I have seen them I am going to look inside all the time, ughhh.